MOSCOW — Russian authorities have launched a criminal investigation into possible violations of air safety regulations following the fatal crash of an An-24 passenger aircraft in the remote Amur region on Thursday, which claimed the lives of all those on board.

The Russian Investigative Committee said Friday that it is exploring several scenarios, including technical failure and pilot error.

Flight recorders recovered from the crash site were found intact and are being transferred to Moscow for analysis.

The Soviet-era aircraft, operated by Angara Airlines, was on a domestic route from Khabarovsk to Tynda when it disappeared from radar just kilometers from its destination.

The plane reportedly failed to issue any distress signals and vanished while attempting a second landing approach.

According to aviation rescue services, the aircraft was flying under challenging conditions, with low cloud cover and mountainous terrain in the area.

However, aviation authorities had earlier described the weather near Tynda as "suitable for receiving flights."

Conflicting reports emerged regarding the number of people on board.

Amur region Governor Vasily Orlov said the plane carried 43 passengers, including five children, while other operational sources reported 40 passengers, including two children.

There were also six crew members aboard, and no survivors have been reported.

Among the victims were foreign nationals, including one citizen each from China and Belarus, according to their respective foreign ministries.

Rescue operations were hampered by the region's dense taiga forests and swampy terrain, forcing responders to rely heavily on aerial reconnaissance.

Debris was ultimately located on a mountainside 16 kilometers from Tynda.

The 50-year-old aircraft had a troubled maintenance record. Since 2018, it had been involved in at least four reported incidents, including wing damage during taxiing.

Despite this, its airworthiness certificate had been extended until 2036.

Airline officials confirmed that the plane underwent routine preflight inspections before takeoff.

In response to the tragedy, the Interstate Aviation Committee has launched a parallel investigation, while the Russian government has established a special commission to oversee the aftermath. A local crisis center has also been activated to coordinate response efforts. — Agencies