MANILA (UPDATE) — Several groups on Saturday filed the first petition before the Supreme Court questioning the just signed Anti-Terrorism Law, saying the measure breaches the constitution.

The petitioners — including a lawyers' group led by Howard Calleja, the De La Salle brothers led by former education secretary Brother Armin Luistro, and civic groups — filed the plea electronically and sought a temporary restraining order against the law.

"While threats to our national security need to be addressed, the law, as crafted, is oppressive and inconsistent with our constitution, hence, the petition," the group said in a Facebook post.

"This fight against terrorism should not and should never be a threat to the fundamental freedoms of all peaceful Filipinos," it added.

BREAKING: A group of lawyers led by Atty. Howard Calleja, the De La Salle brothers led by Brother Armin Luistro and civic groups have filed the 1st petition before the Supreme Court questioning the Anti-Terrorism Act. They ask for TRO to stop its implementation. pic.twitter.com/eb8Xyj7g0B

— Mike Navallo (@mikenavallo) July 4, 2020

Atty. Calleja has yet to provide a full copy of the Supreme Court petition questioning Republic Act No. 11479 or the Anti-Terrorism Act of 2020 which the President signed into law despite growing opposition to the measure.

— Mike Navallo (@mikenavallo) July 4, 2020

Executive Secretary Salvador Medialdea, National Security Adviser Hermogenes Esperon, the secretaries of defense, the interior, finance, justice, and information and communications technology, and the executive director of the Anti-Money Laundering Council were named as respondents.

The group said they would go to the Supreme Court on Monday to physically file the petition.

Calleja has yet to provide a full copy of the plea that alleged 11 sections of the Anti-Terrorism Act were unconstitutional, including those concerned with the definition of terrorism, parameters regarding threats and inciting to commit terrorism, the recruitment of terror organizations, surveillance of terror suspects, designation of individuals and groups as terrorists, and warrantless detention, among others.

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"Petitioners respectfully pray that the Honorable Court would remain steadfast and unwavering in protecting the citizens' fundamental rights, and therefore, not permit the respondents to curtail the same in the guise of the Anti-Terrorism Act," they said in their petition.

WHY ANTI-TERROR LAW STRIKES FEAR

President Rodrigo Duterte signed the law on Friday despite concerns it might stifle basic freedoms and be used to crack down against legitimate dissent.

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

The legislation enables Duterte to appoint a council that could order warrantless arrests of people it deems are terrorists. It also allows for weeks of detention without charge, which the government argues is necessary to combat long-running communist and Islamist insurgencies.

But activists say the definition of terrorism in the legislation is vague and could strengthen Duterte's campaign against critics. Some are already serving prison sentences or facing jail time after attacking his policies including his drug war that has killed thousands.

The law defines terrorism as intending to cause death or injury, damage to government or private property or use of weapons of mass destruction to "spread a message of fear" or intimidate the government.

Critics allege the legislation also strips away old safeguards, such as penalties against law enforcers for wrongful detention of suspects.

"By signing the anti-terrorism bill into law, President Duterte has pushed Philippines democracy into an abyss," said Phil Robertson, deputy Asia director for Human Rights Watch.

"The law threatens to significantly worsen the human rights situation in the Philippines, which has nosedived since the catastrophic 'war on drugs' began four years ago," Robertson added

• READ: The Anti-Terrorism Act of 2020
• Terror law ill-timed? Extremists know no timing, says senator

In a report last month, the UN human rights office said at least 8,663 people have been killed in the drug war with "near impunity" for offenders.

Government officials say alarm about the law is overblown, citing provisions that exempt "advocacy, protest, dissent, stoppage of work... not intended to cause death or serious physical harm".

The National Union of Peoples' Lawyers said it would defer the filing of a separate plea against the law to include more petitioners, tweak portions of the petition, complete requirements and add more substantive issues.

— With reports from Mike Navallo, ABS-CBN News; Agence France-Presse