By Nick Beake & Kostas Kallergis

ATHENS — New evidence found by BBC News casts further doubt on the Greek coastguard's version of events surrounding last month's deadly migrant boat sinking, in which up to 600 people died.

Two survivors have described how the coastguard pressed them to identify nine Egyptians on board as traffickers.

A new video of the overcrowded boat foundering at sea also challenges the Greek coastguard's account.

It was taken when the boat was said to be on a "steady course".

BBC Verify has confirmed the footage was filmed when the coastguard claimed the boat was not in need of rescue -- and was in fact filmed by the coastguard itself.

We have also confirmed that the larger vessel in the background is the oil tanker Faithful Warrior, which had been asked to give supplies to the migrant boat.

The official Greek coastguard account had already been challenged in a BBC Verify report -- but now we have seen court documents that show serious discrepancies between survivors' witness statements taken by the coastguards, and the in-person evidence later presented to a judge.

A translator has also come forward with his account of a people-smuggling investigation last year, after another group of migrants were rescued by the coastguard. He describes how witnesses from that incident were intimidated by the coastguard. The legal case collapsed before it could reach trial.

The revelations raise fresh questions about how the Greek authorities handle such disasters.

Both the Greek coastguard and Greek government did not comment and declined our requests for an interview.

Soon after the 14 June sinking, nine Egyptian men were detained and charged with manslaughter and people-smuggling.

But two survivors of the disaster say migrants were silenced and intimidated by Greek authorities, after suggesting the coastguards may have been to blame for the tragedy.

For the past month, allegations have been made that the coastguard used a rope to tow the fishing vessel, causing it to sink.

The two survivors we spoke to in Athens -- who we are calling Ahmad and Musaab to protect their identities -- say that is what happened.

"They attached a rope from the left. Everyone moved to the right side of our boat to balance it," says Musaab. "The Greek vessel moved off quickly causing our boat to flip. They kept dragging it for quite a distance."

The men described how they spent two hours in the water before being picked up by the coastguard.

When asked how they knew it was that amount of time, Musaab says his watch was still working so he could tell.

Once on land, in Kalamata, they claim the coastguard told survivors to "shut up" when they started to talk about how the Greek authorities had caused the disaster.

"When people replied by saying the Greek coastguard was the cause, the official in charge of the questioning asked the interpreter to tell the interviewee to stop talking," says Ahmad.

Ahmad says those rescued were told to be grateful they hadn't died.

He says there were shouts of: "You have survived death! Stop talking about the incident! Don't ask more questions about it!"

The men say they are scared to speak out publicly because they fear they too will be accused like the Egyptians.

"If there was a fair system in place, we would contribute to this case," says Ahmad.

The men told us they had both paid $4,500 (£3,480) for a spot on the boat. Ahmad's younger brother was also on board. He is still missing.

As well as this testimony given to us by survivors, we have seen court documents which raise questions about the way evidence is being gathered to be presented in court.

In initial statements from five survivors, none mentioned the coastguard trying to tow the migrant vessel with a rope. But days later, in front of a judge, all explained that there had been a failed attempt to tow it.

One initial statement reads:

"A coastguard ship came to help and suddenly the ship capsized and we found ourselves in the water. Then they rescued us with an inflatable boat."

But the same witness later told a judge:

"The Greek ship tied a rope to the front of our ship and began to pull us slowly, but the rope broke... The second time they tied it up, at first we felt like we were being pulled, then our ship keeled over. The Greek ship sped up and we shouted in English: Stop!" was the evidence from the same survivor to an investigating judge

BBC Verify has not spoken to these witnesses and so we can't say why their accounts changed.

The Greek coastguard initially denied using a rope - but later backtracked, admitting one had been used. But it said it was only to try to board the vessel and assess the situation. It said this was at least two hours before the fishing vessel capsized.

Eighty-two people are confirmed dead in the sinking, but the United Nations estimates as many as 500 more lost their lives.

The Greek authorities say the charged Egyptian men are part of a smuggling ring and were identified by fellow passengers. They face up to life imprisonment if found guilty.

Some survivors allege some of the nine suspects mistreated those on board - while other testimony says some were actually trying to help.

But Ahmad and Musaab told us the coastguard had instructed all of the survivors to say that the nine Egyptian men were to blame for trafficking them.

"They were imprisoned and were wrongly accused by the Greek authorities as an attempt to cover their crime," says Musaab.

A Greek Supreme Criminal Court deputy prosecutor is carrying out an investigation, but calls -- including from the UN -- for an international, independent inquiry have so far been ignored. The European Commission has indicated it has faith in the Greek investigation.

But Ahmad and Musaab are not alone in their concerns about the Greek coastguard.

When the nine Egyptian men were arrested in the hours after the shipwreck, it was widely reported as an example of efficient detective work by the Greek authorities.

But for Farzin Khavand it rang alarm bells. He feared history was repeating itself.

He says he witnessed Greek coastguards put two innocent Iranian men in the frame for people-smuggling last year, following the rescue of 32 migrants whose boat had got into trouble crossing from Turkey.

Khavand, a UK citizen who speaks Farsi and has lived in the Kalamata area for 20 years, acted as a translator during the coastguard's investigation into what happened then.

He says the migrants -- 28 from Afghanistan and four from Iran -- explained that they had set off from Turkey and been at sea for eight days before being rescued.

During this time, the Greek coastguard had approached the boat, before leaving, he was told.

Two Arabic-speaking men had abandoned the boat after the engine blew up, Khavand was told by the Afghan migrants. They said that most people on board had taken turns to try to steer the stricken boat to safety -- including the two accused Iranians, who had paid to be on board like everyone else.

"They [the Iranian men] were highly traumatized," Khavand said.

"They were repeating to me that they'd never even seen an ocean before they set off in Turkey. And they kept being told they were the captain and they said: 'We know nothing about the boat. We can't even swim.'"

One of the two accused, a man called Sayeed who was facing a long prison sentence, had been rescued with his young son, explained Khavand.

"I asked him 'Why did you take a six-year-old child on a boat?' And he said the smugglers told us it's only two hours' journey."

Khavand relayed their accounts to the coastguard, exactly as it had been told to him -- but he says when he saw the transcripts, the Afghans' testimony had changed. He fears they altered their stories after pressure from the Greek authorities.

He says the Iranians told him that some of their fellow Afghan passengers had been leaned on by the coastguard to name them as the people-smugglers -- to avoid being "treated unpleasantly", threatened with prison, and being "returned to the Taliban".

The case eventually collapsed. Khavand says he was not willing to assist the Greek coastguard again. He says when Sayeed and his son were released from custody the €1,500 (£1,278) that had been confiscated from them was not returned.

"The scene ended with me thinking I don't want to do this again because they were not trying to get to the bottom of the truth. They were trying to pick a couple of guys and accuse them of being people smugglers."

All of these accusations were put to the Greek authorities by the BBC - but we have received no response. Our request for an interview with Greece's minister of maritime affairs -- who oversees the coastguard -- was also rejected.

Kalamata lawyer Chrysanthi Kaouni says she has seen other criminal cases brought against alleged people smugglers which have troubled her.

She has been involved in more than 10 such cases, she tells us.

"My concerns are around the translations, the way evidence is gathered and - later on - the ability of the defendants to challenge this evidence," she said.

"Because of these three points, I don't think there are enough safeguards according to the international law, and in the end I don't believe justice is done."

A new study has found that the average trial in Greece for migrants accused of people smuggling lasted just 37 minutes and the average prison sentence given was 46 years.

The study, commissioned by The Greens/European Free Alliance group in the European Parliament, looked at 81 trials involving 95 people -- all of whom were tried for smuggling in eight different areas of Greece between February 2020 and March 2023.

The study claims verdicts were reached often on the testimony of a single police or coastguard officer and, in more than three-quarters of the cases, they didn't appear in court for their evidence to be cross-examined.

Ahmad says he and the other survivors now want authorities to recover the shipwreck and the people that went down with it, but they have been told it's too difficult and the water is too deep.

He compares this to the vast amounts of money and resources spent on searching for five people on the Titan submersible in the North Atlantic in June.

"But we were hundreds," he says. "It's not just a ship. It's our friends and family." — BBC