Philippines authorities are reporting that the incident is a 'false alarm'.
Airport officials said that Saudi Arabian Airlines plane sent the distress call by mistake before landing in Manila. The flight was isolated for safety reasons and passengers are now disembarking.
A Saudi Arabian Airlines flight SV 872 from Jeddah has been put into isolation at Manila airport in the Philippines on 20 September. Airport officials have confirmed that the flight is "under threat".
Most of the passengers on the flight are believed to have been returning from the annual hajj pilgrimage. According to CNN Philippines, the control tower received a warning 20 miles before flight landed that it was under threat.
The flight landed in Manila's Ninoy Aquino International Airport at 3pm local time (8am BST) on 20 September. Some social media reports have indicated that passengers have been evacuated safely. Others suggested that the pilot pressed the emergency button by mistake.