MANILA — The Philippine government's use of intelligence funds should be evaluated in the wake of the bombing that hit Mindanao State University (MSU) in Marawi, Lanao del Sur, which killed at least 4 people and injured 50 others, a lawmaker said Tuesday.

"I think this is the perfect time for the country to really revisit what are the things that are being done by using these intelligence funds because ultimately this going to happen again," Lanao del Sur First District Rep. Zia Alonto Adiong told ANC's "Headstart."

"We have to fortify not only within the area, but we also need to collaborate further and intensify our intelligence," he added.

• At least 4 killed after explosion rocks Mindanao State University in Marawi

The blast from an improvised explosive device happened during a Catholic Mass inside the MSU. The Islamic State group has claimed responsibility for the attack.

Adiong said he received reports that authorities identified two persons of interest that could be responsible for the blast.

Security officials earlier said that the attack might have been a retaliatory strike for a series of military operations against Islamist militant groups in recent days.

Pro-Islamic State Maute and Abu Sayyaf militants -- including foreign and local fighters -- held Marawi under siege in 2017.

The Philippine military wrested back the ruined city after a five-month battle that claimed more than 1,000 lives.

"There are strong indications of a foreign element (in Sunday's attack)," Defense Secretary Gilbert Teodoro told reporters.

• Islamic State claims responsibility for Mass bombing in Marawi
• Mindanao lawmakers 'disappointed' over progress of Marawi rehabilitation

—— with a report from Cecil Morella, Agence France-Presse