Manila: An official of the Office for Transportation Security (OTS) on Monday called on airport passengers to immediately report any suspicious activities, after noting the agency has been receiving hoax threats.

According to Philippines News Agency, "We have been receiving threats through phone calls, email, Facebook. We check these in coordination with airport security and the Philippine National Police," OTS Administrator Gilbert Cruz said during a Bagong Pilipinas Ngayon interview.

Cruz said all these threats were found to be hoax, and raised the possibility that dismissed airline employees and airport security personnel may be behind some of those threats.

He said the agency is ready to combat these incidents, saying OTS personnel regularly undergo training.

"We also have a group chat with security providers of every airport to ensure swift response to threats," he added.

Meanwhile, Cruz urged passengers to immediately report any suspicious activity or things at the airport.

"Once they notice anything suspicious, or an unattended bag, report these immediately so these can be resolved fast," he added.