MANILA (UPDATED) — President Ferdinand Marcos Jr. on Sunday called for calm in the wake of an explosion at a gymnasium in Marawi City where people were hearing Mass and that has left four dead.

In a statement, Marcos condemned the blast at the Mindanao State University's Marawi campus, which he attributed to "foreign terrorists." He warned that "extremists who wield violence against the innocent will always be regarded as enemies to our society."

The Philippine National Police, in a separate statement, said it is working to identify who is behind the blast.

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

Marcos said the national government is in close coordination with the regional government of the Bangsamoro Autonomous Region in Muslim Mindanao and with local government units in the aftermath of the explosion.

The armed forces and the national police have also been instructed to ensure the safety and security of communities in the area, with additional security personnel being deployed.

According to the PNP, it has placed its Police Regional Offices — including in the National Capital Region — on full alert and will be deploying more patrols and putting up more checkpoints as a deterrent to other possible attacks.

It has also deployed augmentation teams of Special Action Force, Explosive Ordnance Disposal and K9 personnel to areas of Marawi City.

CALL FOR CALM

"As reports come in throughout the day, I enjoin all of us to remain calm, circumspect and conscientious in our collective efforts to ensure that the horrific events of this morning are not further compounded by inaccurate, unvetted and unofficial information," he also said.

In a statement, conflict monitor Climate and Conflict Action Asia also warned that is is "too early to draw conclusions or to point fingers towards any individual or group."

The group called for calm "amidst attempts to polarize the situation and sow the seeds of a Muslim-Christian conflict" as it said that it has monitored hate speech on the ground and in social media in the aftermath of the blast.

"As we mourn the loss of those who have perished, let us unite and work hand in hand so that we can help prevent such incidents from happening again, as we continue to promote the culture of peace, mutual understanding, and solidarity across our nation," presidential peace adviser Carlito Galvez Jr., who is a former commander of the military Western Mindanao Command that operates in the BARMM, said in a separate statement.

DIPLOMATS SEND CONDOLENCES, SOLIDARITY

The diplomatic corps was quick to send messages of condolences and solidarity on Sunday, with EU Ambassador Luc Veron calling the explosion "deeply disheartening."

He added: "Violence has no place in schools."

US Ambassador MaryKay Carlson also extended condolences on behalf of her government, adding that "[w]e condemn this act of violence and support efforts to hold the perpetrators accountable."

The French Embassy meanwhile assured "the authorities and the Filipino people of our solidarity in the face of this despicable terrorist attack."

Japanese Ambassador Koshikawa Kazuhiko, in a message, "[reiterated] Japan’s commitment to support the peace process to achieve sustainable peace and stability in Mindanao."

'NO ROOM FOR PERPETRATORS'

Lanao del Sur Gov. Mamintal Alonto Adiong Jr. condemned the blast earlier Sunday, saying "we uphold basic human rights, and that includes the right to religion" in the province.

"Terroristic attacks on educational institutions must also be condemned because these are places that promote the culture of peace and mold our youth to be the future shapers of this country,” he also said.

Lanao del Sur 1st District Rep. Zia Alonto Adiong, the governor's brother, has also condemned the yet to be named perpetrators of the attack.

"There is no room in Marawi, in Lanao del Sur, or in the entire Philippines for them."