ALL 42 commercial airports in the country were put on heightened alert by the Civil Aviation Authority of the Philippines (CAAP) after an anonymous email received by the Air Traffic Service said there were bombs that could go off in aircraft from Manila bound for certain domestic destinations.

An advisory was released by CAAP on Wednesday but was only made public on Friday through the Facebook page of a non-government organization called the Philippine Emergency Alerts.
The email said there were aircraft at the Ninoy Aquino International Airport (NAIA) bound for 'Puerto Princesa, Mactan-Cebu, Bicol, and Davao international airports' that were timed to 'set off.'
Aviation authorities said the information was 'being validated but enhanced security measures in all airports shall be immediately implemented.'