Fire alarms sent a Singapore Airlines Boeing 777-200 back to Beijing airport on January 24, less than two hours after the aircraft took off.

No one was injured during the incident and investigators found no sign of a fire or increased temperature on the aircraft, the airlines said.

The plane took off from Beijing at 8:35am with 227 passengers and 16 crew members bound for Singapore.

After one hour and 40 minutes in the air, a fire siren on the right engine started to alarm and the pilots immediately returned the plane back to Beijing at full speed, the carrier said.

"There wasn't a fire and we are still investigating why the siren alarmed," said Wang Yong, a public relations official with Singapore Airlines (China).

One possible reason is the air current disturbed the heat insulation, which caused the siren to give wrong signals, he said.

The plane will be left in Beijing until all checks are finished.

The carrier said it is trying its best to assist the affected passenger to take other flights to Singapore or their final destinations.