MANILA - Sen. Francis "Kiko" Pangilinan said Sunday he would file a petition before the Supreme Court questioning supposed unconstitutional provisions of the Anti-Terror Law.

The opposition senator said these include the law's broad definition of terrorism and the possible detention of suspected terrorists up to 24 days.

"We have to exhaust all remedy. Whether we win or not, is another thing altogether, but we have to fight," he said in a radio interview.

"Sabi ko nga, hindi pa tapos ang boksing at tuloy-tuloy ang ating pagtutol dito at pinaghahandaan natin ang pagsampa ng isang petisyon sa Korte Suprema."

(As I said, the boxing is still not over and we continue to oppose this by preparing for the filing of a petition before the Supreme Court.)

Several groups on Saturday filed the first petition questioning and seeking a temporary restraining order against the law, which President Rodrigo Duterte signed last Friday.

• Anti-terror law faces first Supreme Court challenge

Pangilinan cited the anti-terrorism council's power to issue a written authority to detain a suspected terrorist for up to 24 days under Section 29 of the law.

"‘Yan, dapat ‘yan sa hudikatura. At ‘yung Saligang Batas sinasabi that no warrant of arrest shall be issued, ‘di ba, except upon probable cause determined personally by a judge," he said.

"‘Yan, presumption of innocence nawala na, ‘di ba? Pinapatunayan mo pang hindi ka terorista pero ikaw ay naka-detain at ikaw ay frozen na ang assets, ‘di ba? So ‘yan, concern din ‘yan. Also, yung issue ng—yun na nga, designation and proscription of terrorist organizations and groups."

The senator urged government to instead focus on addressing the COVID-19 pandemic.

"Last point ko na lang, ang problema natin COVID. Ang problema natin kagutuman. Ang problema natin, paano natin maililigtas ang ating mga sarili at mahal sa buhay dito sa COVID.

"Pero ang binibigay sa ating solusyon o kaya aksiyon, inuuna iyong pagsara ng ABS-(CBN), inuuna itong anti-terror bill, salungat sa mga daing ng ating mga kababayan. At iyong mga nagdadaing kinukulong pa. Hindi tama, hindi tama, kailangang tutulan. Sabi ko nga, hindi man natin maipanalo ito, hindi ibig sabihin hindi tayo dapat tututol at lalaban."

Pangilinan hit government's "iron fist" in dealing with the nation's issues, citing its anti-narcotics campaign, smuggling and corruption at the Bureau of Customs, the martial rule in Marawi, and its COVID-19 response.

"Hindi kamay na bakal ang solusyon sa problema ng COVID, sa solusyon ng problema ng terorismo, sa solusyon sa problema ng droga," he said.

"Kinakailangan komprehensibo, hindi puro pananakot, hindi puro pagmumura, hindi puro pagkulong. Hindi ho ganun ang solusyon sa malubhang problema ng ating bansa.

The senator cited a de-radicalization program in Malaysia, where he said rebels undergo values formation.

"Over 200 na mga Abu Sayyaf ay nagbalik-loob precisely because hindi kamay na bakal ang ginamit, kundi komprehensibong programa na kasama ang pagtugon sa problema ng kahirapan," he said.

The law faces heavy opposition over fears it could be used to silence government critics.

• Duterte signs anti-terror bill into law despite growing opposition

Justice Secretary Menardo Guevarra said the law may take effect July 19, 15 days after publication on the Official Gazette on July 3.

• Anti-terror law takes effect on July 18; Supreme Court fight looms

On Saturday, 11 anti-terror law protesters were arrested in Laguna.

• 11 Anti-Terror Law protesters arrested in Laguna