Manila, Apr 27 (IANS): One pilot was killed and three crew members were injured as a Philippine Air Force (PAF) helicopter crashed into the waters off Getafe town in central Philippine Bohol province on Tuesday morning, the military said.

Lt. Col. Maynard Mariano said that the MD520MG attack helicopter was on a maintenance flight when it went down at around 9:30 a.m. local time.

Mariano said that the aircraft from the PAF 15th Strike Wing took off from an air force base on nearby Mactan Island in Cebu province.

An investigation is underway to determine the cause of the accident, said Mariano, adding that the PAF decided to ground its MG520 fleet while the investigation is ongoing, the Xinhua news agency reported.

"(The PAF) assures the public that all of its air assets are undergoing strict, regular, and redundant maintenance inspections before and after flight missions," Mariano said.

This is the second PAF helicopter crash this year. Seven soldiers died in a UH-1 "Huey" aircraft crash in Bukidnon province in the southern Philippines on January 16.