Quezon City Local Police Chief Remus Medina said the shooting appeared to have been the assassination of former mayor of the southern city of Lamitan, Rose Foregay.
Medina told reporters that the suspect, who was wounded in a shootout with a security officer on campus and arrested after a car chase, is now in custody and is being questioned.
“It appears he was a determined killer,” Medina said, adding that he was found with two pistols.
Quezon is part of the Metropolitan District of Manila, which is an urban sprawl of 16 cities with a population of over 13 million people.
Furigay was shot while about to attend her daughter’s graduation from Ateneo de Manila University of Law, one of the most prestigious universities in the country, according to a city.
The suspect, who had no relatives upon graduation, was a native of Lamitan city in Basilan province, a stronghold of Abu Sayyaf, a pro-Islamic State extremist group notorious for its banditry and kidnappings.
Police said the other two dead were a security officer at the campus and an unidentified man.
Ateneo canceled his graduation ceremony after the shooting.
In the Southeast Asian country, shootings have been sporadic, with owners being required to have permits to carry guns in public. Private security officers in the Philippines carry either pistols or rifles, and firearms are a common sight in shopping malls, offices, banks, restaurants, and even schools.
“We compel our law enforcement agencies to conduct a thorough and prompt investigation into these killings and to bring to justice all those involved,” Philippine President Ferdinand Marcos Jr. said in a statement.
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