Philippine President Ferdinand Marcos Jr has ordered an investigation into a school shooting in the city of Tacloban that killed three people and injured five others.

"The president is saddened by the incident," his office said in a statement on Monday, adding he had ordered a thorough investigation and directed authorities to ensure safety and security in all areas, offices and establishments, especially schools.

Police said the two suspects were arrested after the shooting at the San Jose National High School in Tacloban, a city on the island of Leyte about 580km southeast of the capital Manila.

The shooting occurred about 9am local time (0100 GMT) inside the school in Barangay San Jose, the Tacloban City Police Office said, adding an investigation was under way to determine the circumstances behind the incident.

Tacloban police chief Noelito Getigan told reporters the suspects used a .38-calibre and 9mm firearm in the shooting.

One suspect, a minor and grade 9 student, was arrested shortly after the incident, while the other later surrendered to authorities, Getigan said.

Police said the victims were transported to nearby medical facilities for treatment, while additional personnel have been deployed at the school to ensure the safety of students, staff, parents and the surrounding community.

Authorities urged the public not to disseminate unverified information and to co-operate with investigators.

The incident is unusual in the Philippines, where school shootings happen only sporadically.

In July 2022, a gunman opened fire at an Ateneo de Manila University law school graduation ceremony in Quezon City, killing three people including former Lamitan City mayor Rose Furigay.

with AP