MOSCOW, Russia - Russia opened an investigation Friday after a passenger aircraft was forced to land due to a technical malfunction, the latest incident to highlight safety concerns in Moscow's aviation industry.

Sanctions over the conflict in Ukraine have effectively cut Russia off from Western plane manufacturers Airbus and Boeing, making it difficult for Russian airlines to import and maintain plane parts.

The plane, a Boeing 737-800 operated by S7 airlines, was travelling from the Siberian city of Novosibirsk to Moscow on Friday before an engine failure forced it to turn back to the airport, investigators said.

"The landing was made safely. There were no casualties. The causes and circumstances of the accident are being established," they added.

In a separate incident the day before, a Tu-204 cargo plane was forced to land in Siberia due to an engine fire.

The majority of planes operated by Russian airlines are made by either Airbus or Boeing, Western companies that have stopped doing business with Russia.

The Kommersant newspaper reported in October that S7 would reduce its autumn/winter flight schedule by 10-15 percent due to difficulty servicing the engines on its Airbus planes.