JAKARTA: A lawmaker involved in vetting Indonesia's proposed counter-terrorism law says a contentious provision allowing detention without trial for six months could undermine the fight against Islamic extremism.

Hanafi Rais, vice chairman of the parliamentary committee debating the current draft of the law, said Tuesday that permitting lengthy detention in undisclosed prisons would give security forces powers that could be easily abused.

Speaking at a panel on extremism, Rais said parliament should pass a law that strengthens the capacity of police to prevent attacks without giving the state excessive power that could foster support for radicals.

He said lawmakers were "stunned" by the death of suspected militant Siyono in police custody earlier this year, which revealed a lack of professionalism in Indonesia's elite counter-terrorism squad.

Efforts to strengthen laws against militant activity gathered momentum after a suicide bombing in the Indonesian capital in January which killed eight people, including four attackers who claimed allegiance to the Islamic State group.

It was the first major attack by extremists in the world's most populous Muslim nation in six years and raised questions about whether the country was facing a new threat despite the sustained crackdown that decimated the Jemaah Islamiyah network responsible for the 2002 Bali bombings.

Rais said the new law could be ready for parliament to vote on in October. He predicted there would be a "tough" debate that could result in a reduction to the six-month detention provision.