A protest against government corruption turned violent Sunday, resulting in the arrest of 17 people, injuries to dozens of police officers, and an attack on a journalist.

The Philippine National Police (PNP) said a group of about 400 demonstrators gathered in Mendiola when some individuals began throwing stones and Molotov cocktails at riot police and set fires.

The PNP confirmed that some of the arrestees are minors.

Police said 39 officers were hurt in the confrontation, with two remaining hospitalized.

“Seventeen individuals believed to be responsible are now in the custody of the Manila Police District,” the PNP said in a statement, adding that appropriate charges are being prepared.

The violence erupted when masked individuals in black clothing threw rocks, bottles, and paint at police guarding the road to Malacañang Palace.

Videos of the incident show some figures kicking police riot shields on Ayala Bridge, while others set fire to tires on a parked trailer truck being used as a police barricade.

A radio reporter was also struck in the face by a rock while livestreaming the protest on Facebook.

In line with this, the Presidential Task Force on Media Security (PTFoMS) condemned the attack on Vargas, saying it “highlights the urgent need to protect journalists.”

“This incident highlights the urgent need to protect journalists, whose work is essential in ensuring the public’s right to accurate and timely information,” PTFoMS executive director Jose Torres Jr. said.

Meantime, the PNP said it is still investigating the affiliations of the protesters, some of whom carried a flag with the “Straw Hat Pirates” Jolly Roger from the Japanese manga series “One Piece.”

“The PNP remains committed to safeguarding both the public and demonstrators,” the police said.

“We will continue to exercise maximum tolerance, but we will also act against anyone who causes harm or damages property,” it added.