Manila, March 16 -- Malacanang on Monday clarified that the security activity observed near the Palace complex was just part of a routine exercise to test the readiness of security personnel.

Palace Press Officer and Presidential Communications Office Undersecretary Claire Castro made the clarification after photos circulating on social media showed an apparent increase in security presence near Mendiola, prompting speculation that Malacanang had been placed under heightened alert.

"It is just part of a security exercise to test the operational readiness of personnel and units," Castro told reporters.

The clarification came after some social media users and commentators claimed the Palace was on "full alert," following the circulation ...