MANILA (3rd UPDATE) - President Rodrigo Duterte on Friday signed into law a bill that seeks to sharpen the Philippines' anti-terrorism campaign despite heavy opposition over fears it could be used to silence government critics.

Republic Act No. 11479, or the Anti-Terrorism Act of 2020, was signed just days before it was to lapse into law. Congress on June 9 transmitted the bill to Malacañang for President Duterte's signature.

"The signing of the aforesaid law demonstrates our serious commitment to stamp out terrorism, which has long plagued the country and has caused unimaginable grief and horror to many of our people," Presidential spokesman Harry Roque said in a statement.

"As we have said, the President, together with his legal team, took time to study this piece of legislation weighing the concerns of different stakeholders," he added.

• Congress transmits Anti-Terror bill to Palace for Duterte's signature

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Critics have called out the bill, which adds muscle to the 2007 Human Security Act, on fears that it could be abused to violate basic rights due to the broad definition of "terrorism."

Those against the bill have used the hashtag #JunkTerrorBill to show their opposition to the measure. Several groups have also launched signature campaigns calling for the scrapping of the bill.

"Terrorism, as we often said, strikes anytime and anywhere. It is a crime against the people and humanity; thus, the fight against terrorism requires a comprehensive approach to contain terrorist threat," Roque said.

Earlier this week, UN High Commissioner for Human Rights Michelle Bachelet called on President Rodrigo Duterte to "refrain" from signing the controversial measure, citing its potential "chilling effect" on humanitarian and human rights work.

• UN rights chief urges Duterte to 'refrain' from signing anti-terror bill

The stricter anti-terror law comes as the Philippines continued efforts to stop terror activities, including kidnappings and bombing operations of the Islamic State-linked Abu Sayyaf group, extremists that the United Nations tagged as terrorists in 2001.

In 2017, the Duterte administration had to quell a 5-month siege waged by local terror group Maute, also linked to ISIS, in the southern city of Marawi. The prolonged firefights left over 1,000 people dead, mostly terrorists, and reduced the Islamic city in shambles.

AFP spokesperson Major General Edgard Arevalo said the military looked forward to the President enacting the bill, which specifically targets terrorists.

"We now have a powerful statute that provides law enforcement agencies the legal wherewithal to protect and defend our people," he said in a statement.

Read the full measure below: