The Southeast Asian bloc ASEAN has strongly condemned what it calls a "heinous terrorist attack" in the southern Philippines in which four people were killed in a bombing at a Catholic mass. The bomb went off on Sunday during a service at a university gymnasium in Marawi, a city left in ruins in 2017 by a five-month military campaign to end an occupation by Islamic State loyalists that triggered alarm in Asia about the group's influence. "We extend our deepest condolences to the bereaved families," the Association of Southeast Asian Nations (ASEAN) said in a statement on Friday. Islamic State militants claimed responsibility for Sunday's attack. President Ferdinand Marcos Jr said "foreign terrorists" were behind it and police said they were investigating the incident and validating the claim by the Islamic State group. Police had identified as suspects two members of Daulah-Islamiyah Maute, a local group involved in the 2017 seizure of Marawi alongside fighters from Indonesia, Malaysia and beyond. The Philippine military on Friday announced the December 6 arrest in Marawi of a man suspected of placing the bomb in the gymnasium. They said the man had been identified by witnesses. Australian Associated Press