Senators on Friday lauded the arrest of the alleged accomplice in the bloody bombing at the Mindanao State University in Marawi City that killed at least four people and injured 50 others, after the Armed Forces of the Philippines said that one of the suspects, identified as Jaffar Gamo Sultan, was arrested in Barangay Duay Proper in Marawi City.

Sultan is tagged as one of the companions of a certain Omar, the person who took the improvised explosive device to the Catholic liturgy at the Dimaporo Gymnasium on 3 December.

"We applaud our law enforcers' arrest of one of the MSU bombing suspects, and urge them to persist until they find the masterminds of this hideous crime," Senator Imee Marcos said in a statement.

Marcos also urged people to "work together for a lasting peace and genuine development in Mindanao."

"Let us not allow corrupt officials to exploit this tragedy, as they have exploited such tragedies in the past, for their own personal gain," she added.

Meanwhile, Senate Minority Leader Aquilino "Koko" Pimentel III reminded authorities to respect the rights of suspects behind the explosion in Marawi.

"I encourage the Philippine National Police and law enforcement agencies and the entire government to conduct a swift but thorough investigation on the recent Marawi-MSU bombing," Pimentel said in a separate statement.

"Follow the evidence and charge those where the evidence leads, always remembering that these people are presumed innocent until proven guilty and their rights should be respected all the time," he added.

Islamic State militants earlier claimed responsibility for the deadly attack in Marawi, which was once occupied by the Maute group for several months in 2017.

In the message application Telegram, the group admitted the attack, claiming its members had detonated the bomb.