KABUL — A suicide bomber in Afghanistan killed about 20 people and wounded dozens on Tuesday at a gathering on the highway between the eastern city of Jalalabad and the main border crossing into neighboring Pakistan, officials said.

The blast, less than a week after a suicide attack that killed more than 20 people in the capital, Kabul, came as violence has flared across Afghanistan, with heavy fighting in northern provinces over recent days.

There was no immediate claim of responsibility for the attack, which the provincial governor’s office said killed at least 19 people and wounded 57 more, although the total remains unclear, amid conflicting official reports.

Sohrab Qaderi, a member of the Nangarhar provincial council, said at least 30 bodies had been taken to hospital, but the toll could rise.

Nangarhar, one of the main strongholds of Daesh (the so-called IS) fighters since early 2015, has been one of the most volatile regions this year, with a string of suicide bombings and attacks on its capital, Jalalabad.

Officials and elders said Tuesday’s attack targeted a gathering to protest against a local police commander, adding that hundreds of people were present when the blast happened.

Qaderi said rescue efforts were being hampered by reports of another suicide bomber in the area, making police and emergency services cautious about approaching the scene.

The explosion followed a series of smaller blasts on Tuesday that targeted schools in Jalalabad and surrounding districts, killing at least one person and wounding three.

An unprecedented ceasefire in June followed by talks between US officials and Taliban representatives in Qatar in July raised hopes that peace negotiations could bring an end to the fighting.

There has been speculation the two sides will meet again this month.

The Taliban have long insisted on direct talks with Washington and refused to negotiate with the Afghan government, which they see as illegitimate.

But newly appointed US envoy Zalmay Khalilzad has canceled further talks with the militants until he has reviewed the American strategy, a Western official in Kabul said on the condition of anonymity.

The information could not be immediately confirmed. One militant source, a senior Taliban commander based in neighboring Pakistan, had said he expected more talks to be held “soon”.

The intensified fighting has also fueled speculation over whether Afghanistan’s long-delayed parliamentary elections will go ahead on Oct. 20.

The country’s already overstretched security forces will be tasked with protecting thousands of polling stations around the country at a time when they are already struggling to beat back insurgents.

Delivering ballot papers and monitoring the vote, which is seen as a test run for next year’s presidential election, will be challenging, officials have warned.

In the past two days Taliban fighters killed nearly 60 members of the security forces in a spate of attacks in the country’s north and threatened a provincial capital for the second time in as many months.

After seizing a military base in Sar-e-Pul, Taliban fighters were closing in on the provincial capital in a situation that could result in “disaster” if reinforcements were not sent, the area’s police chief Abdul Qayom Baqizoy warned on Monday.

Baqizoy compared the threat to the Taliban’s extraordinary raid last month on the provincial capital of Ghazni —fighters held large parts of the city located just two hours from Kabul for days.

On Tuesday security forces had managed to push back Taliban fighters by a couple of kilometers, locals and officials said. — Agencies