Malaysia Airlines today explained the turn-back of its Flight MH179 last night was due to an "intoxicated" passenger who was being disruptive on board the aircraft.

"The intoxicated passenger started harassing Malaysia Airlines' crew shortly after the flight was airborne. 

"Due to his big body size, other guests had to assist the crew to restrain the passenger," it said in a statement today.

MAS added that the commander of the flight decided to turn back the aircraft in the interest of the safety and comfort of those on board.

"Upon arrival at KL International Airport (KLIA), the disruptive passenger was handed over to the authority," it said.

Flight MH179 took off from KLIA at 11.27pm and was supposed to arrive in Colombo at 12.18am Sri Lankan time.

However, it sparked an online frenzy after flight trackers showed Flight MH179 flying in circles over the ocean west of Pulau Ketam since about 11.30pm.

The practice is common to burn extra fuel if an aircraft plans to land earlier than expected.

It eventually landed in KLIA some 20 minutes later.­

MAS said the flight was rescheduled and renamed MH179D which finally took off from Kuala Lumpur for Colombo today at 10.06am.