MARSEILLE, March 24 (Reuters): An Airbus plane operated by Lufthansa's Germanwings budget airline crashed in southern France on Tuesday en route from Barcelona to Duesseldorf, police and aviation officials said.

French Prime Minister Manuel Valls said he understood between 142 and 150 people were on board and feared dead.

”The cause is at present unknown,” he told reporters.

A spokesman for the DGAC aviation authority said the airplane crashed near the town of Barcelonnette about 100 km (65 miles) north of the French Riviera city of Nice.

Lufthansa's Germanwings unit said it was as yet unable to verify reports of the crash.

The crashed A320 is 24 years old and has been with the parent Lufthansa group since 1991, according to online database airfleets.net