Manila, Sep 20 (IANS): A Saudi Arabian passenger plane, with 300 persons on-board, triggered fears of a hijack today in Manila after mistakenly making a distress call.

The plane, which landed at the Ninoy Aquino International Airport here, was held in isolation, media reported.

Before landing, the plane's pilots reportedly told the Manila control tower that the plane was "under threat" and asked for emergency assistance, saying emergency 4 -- a code that could mean possible hijacking in airline jargon, Xinhua news agency reported.

The alarm followed the pilot having reportedly pressed a hijack "panic button" twice. According to CNN Philippines, the control tower received a warning 32 kms before flight landed that it was under threat.

The passengers of Saudi Arabian Airlines flight SV 872, which took off from Jeddah shortly before midnight, later went through security checks as a matter of routine.

Most of the passengers on the flight are believed to have been returning from the annual Hajj pilgrimage.