A Russian passenger aircraft carrying 246 people made a successful emergency landing at Lanzhou Zhongchuan International Airport in Gansu province on Friday after issuing a distress signal while flying over Chinese airspace, airport authorities said.

The Azur Air flight, ZF2998, was en route from Phuket International Airport in Thailand to Barnaul in Russia when the crew declared an emergency and activated transponder code 7700, the international distress signal. Flight-tracking data showed the aircraft circled near Lanzhou and jettisoned fuel as a precaution before landing.

The Boeing 757-200 touched down safely at 4:51 pm local time. All 239 passengers and seven crew members on board were unharmed, the airport said.

Normal takeoff and landing operations at the airport were not affected. The airport said it is organizing follow-up coordination work related to the incident.