MANILA - A supposed bomb threat jolted four schools in the vicinity of Malacañang Palace in San Miguel, Manila before classes started on Monday morning.

After a thorough sweep, authorities eventually confirmed that they found no bombs at the Centro Escolar University (CEU), San Beda College, Eulogio "Amang" Rodriguez Institute of Science and Technology (EARIST) and the College of the Holy Spirit-Manila (CHSM).

The EARIST on Sunday night was first to receive the bomb threat, which prompted the Manila Police District (MPD) Explosive and Ordnance Division to comb through its campus.

The CEU, CHSM and San Beda College -- all located in the Mendiola district -- were rocked by the bomb hoax on Monday morning.

At 4:34 a.m. the CEU received a Facebook message from a supposed member of the extremist Abu Sayyaf Group (ASG), saying that bombs had been planted in its campus, as well as the San Beda College and two other schools.

JUST IN: CEU,nakatanggap din ng bomb threat sa pamamagitan ng Facebook | via @Dennis_Datu pic.twitter.com/e2WkI3h1B1

— DZMM TeleRadyo (@DZMMTeleRadyo) September 5, 2016

The CHSM, meanwhile, received a call and text at 7 a.m. claiming that an explosion will occur at the school.

Due to the threat, the school suspended its classes from the elementary to college levels.

JUST IN: Bomb threat sa College of the Holy Spirit Manila; klase, suspended na | via @Dennis_Datu pic.twitter.com/jg8FLw7vJO

— DZMM TeleRadyo (@DZMMTeleRadyo) September 5, 2016

After bomb squads swept through the three schools, MPD Station 8 commander Superintendent Olive Sagaysay declared their campuses safe at 9 a.m.

Sagaysay said police will boost security visibility in the U-Belt area.

Monday's bomb hoax comes in the heels of a Friday night explosion that killed 14 people and injured at least 67 others at a night market in Davao City. -- Report from Dennis Datu, DZMM