The Bureau of Immigration (BI) is on “heightened alert” to prevent foreign terrorists and human traffickers from taking advantage of the long weekend.

In a memorandum issued to all international airports and seaports, Immigration chief Ricardo David Jr. directed immigration personnel to be “extra-vigilant” and to subject under a “secondary inspection” all tourists whose purpose in visiting the Philippines is “doubtful.”

Foreigners entering the country who are considered as a threat to national security or are blacklisted by the government “shall be excluded and booked on the first available flight to his or her port of origin.”

Immigration acting intelligence chief Maria Antonette Bucasas-Mangrobang said foreign terrorists and human traffickers should be warned that they are “off-limits” to the country’s ports.

“We cannot relax our vigilance during these periods when the country’s attention is focused on the observance of a religious tradition, adding that “alien terrorists and human traffickers should be served notice that our ports are tightly guarded daily,” she said.