By Phil Mercer BBC correspondent in Sydney

The Australian Government is preparing new laws to give its domestic intelligence agency increased powers to detain and interrogate terrorist suspects.

A parliamentary inquiry has claimed the changes will seriously erode the rights of individuals, while civil liberties groups have also expressed concern.

People know that overseas there have been people under the age of 18 who've been involved in suicide bombing exercises

Daryl Williams, Attorney General

The conservative government has already watered down parts of its original proposal, but is insisting its spy agency must have robust powers to gather intelligence that could stop bombings or other acts of terror on Australian soil.

The new laws are due to be debated in parliament this week before it closes for the summer recess.

11 September legacy

It was the attacks 11 September attacks in New York and Washington that prompted the government to give broader powers to the Australian Security Intelligence Organisation (ASIO).

The bombings in Bali in October that killed almost 200 people, including many Australians, gave added weight to those pushing for the new legislation to be introduced.

A suspect's right to silence will be waived

The changes would allow ASIO to detain and question suspects for up to seven days. Their right to silence would be removed and access to lawyers limited.

The original bill provided for the detention and even strip-searching of children.

Under pressure from backbenchers from both the opposition and the government, ministers have agreed to drop the idea - but only in part.

Detention of teenagers

The current proposals still allow for 14-year-olds to be detained. The Attorney-General, Daryl Williams, says if young teenagers are thought to have important information, they will be questioned.

I don't think that children should be subject to any new additional interrogation regime

Professor George Williams, University of New South Wales

"People know that overseas there have been people under the age of 18 who've been involved in suicide bombing exercises," Mr Williams said.

"If that were to occur here, there would be people with information that we would need to know about to prevent a bombing taking place," he added.

Muslim organisations in Australia are worried that the new security measures are part of a wave of anti-Islamic sentiment which has swept the country since the attack in Bali.

Human rights issue

Civil liberties groups have described the new powers as a "massive breach of human rights".

One campaigner said he believed reactionary politicians were cynically misusing the events of 11 September to create a police state.

A Brisbane mosque was attacked after the Bali bomb

A report by members of the Upper House, the Senate, is also critical of the changes. While it accepts the role of the security agency to carry out interrogations, it believes they should be supervised by retired judges.

The senators say legal representation should be available immediately and that the bill must not apply to anyone under 18.

Draconian measures

Professor George Williams from the University of New South Wales agrees that youngsters should be excluded from the new measures.

"If a child was involved in terrorism, they would be covered by the existing criminal law. They could be held, they could be questioned, they could be charged and they could be convicted," he said.

"That's an appropriate balance. I don't think that children should be subject to any new additional interrogation regime," Professor Williams added.

The government is insisting it is not willing to make any more changes to its new security legislation.

The main opposition Labor Party believes further amendments need to be made to protect civil rights, but is worried that continued hardline resistance to the bill will make it look like it has gone soft on terrorism.