Police arrested 17 terror suspects in Australia's two biggest cities Tuesday in raids authorities said foiled a plot to carry out a catastrophic terror attack. A radical Muslim cleric known for praising Usama bin Laden was charged with masterminding the plot.

More than 500 police backed up by helicopters were involved in raids across Sydney and Melbourne, arresting eight men in Sydney and nine in Melbourne and seizing chemicals, weapons, computers and backpacks.

One suspect was in critical condition after being shot in the neck during a gunfight with police, said police Commissioner Graeme Morgan. An officer was also slightly wounded.

One of the suspects wanted to die a martyr, a police officer said in court.

"I'm satisfied that we have disrupted what I would regard as the final stages of a large-scale terrorist attack ... here in Australia," New South Wales Police Commissioner Ken Moroney told Australian Broadcasting Corp. radio.

He later said he expected more arrests "in coming days and weeks."

Late Tuesday night, police raided another Sydney home as part of the terror probe, an Australian Federal Police spokesman said on condition of anonymity per government policy. There were no immediate arrests.

Prime Minister John Howard, who last week warned of a possible terror attack in Australia, thanked security forces in a nationally televised news conference.

"This country has never been immune from a possible terrorist attack," he said. "That remains the situation today and it will be the situation tomorrow."

Abdul Nacer Benbrika, aka Abu Bakr, an Algerian-Australian who has said he would be violating his faith if he warned his students not to join the jihad, or holy war, in Iraq, was among nine men who appeared Tuesday morning in Melbourne Magistrates Court charged with being members of a terror group.

Prosecutor Richard Maidment told the court the nine planned to kill "innocent men and women in Australia."

"The members of the Sydney group have been gathering chemicals of a kind that were used in the London Underground bombings," Maidment said. "Each of the members of the group are committed to the cause of violent jihad."

He said they underwent military-style training at a rural camp northeast of Melbourne.

Seven of the suspects, including Abu Bakr, were ordered detained until a court appearance on Jan. 31. Two others were to hear Wednesday whether their application to be released on bail was granted.

Detective Sergeant Chris Murray told the court police surveillance had picked up one suspect, 20-year-old Abdulla Merhi, pleading for permission to become a martyr during discussions with other suspects.

Murray said it was clear to police he wanted to die "similar to the nature of a suicide bomber."

Seven men arrested in Sydney were held in cells at a tightly guarded downtown court during a five-minute hearing Tuesday afternoon at which they were ordered held until another hearing on Friday on charges of preparing a terror act by manufacturing explosives.

The eighth Sydney suspect, the man shot by police, was under guard in hospital and was not immediately charged.

Defense lawyer Adam Houda, who was representing at least one suspect, told reporters outside the court that the charges were a "scandalous political prosecution."

"There's no evidence that terrorism was contemplated or being planned by any particular person at any particular time or at any particular place," he said.

Federal Police Commissioner Mick Keelty said the fact that a suspect fired at police "serves to show that we are dealing with very serious issues here."

Angry supporters of the suspects clashed violently with news cameramen in Melbourne and Sydney.

Moroney said possible bomb-making materials were found during the raids, including chemicals which, "when combined in combinations of one or more, certainly could be highly volatile."

Police declined to give details of the likely target of the attack, but New South Wales Police Minister Carl Scully said: "I was satisfied that this state was under an imminent threat of potentially a catastrophic terrorist act ... involving the attempted stockpiling of chemicals and related materials that could be used in a major explosion."

Melbourne lawyer Rob Stary said he represented eight of the Melbourne suspects including Abu Bakr, who in the past has called Al Qaeda mastermind Usama bin Laden a "great man." Abu Bakr leads a fundamentalist Islamic group in the southern city of Melbourne where he has lived since 1989.

Australia has never been hit by a major terror attack, but its citizens have repeatedly been targeted overseas, particularly in neighboring Indonesia, where dozens of Australians have been killed in bomb blasts since 2002.

Last week, Howard rushed through Parliament an amendment to terror laws he said would beef up police powers to arrest suspects plotting attacks. Melbourne police said the new powers helped them carry out their raids.

Opponents say Howard's strong support for the U.S.-led strikes on Iraq and decision to send troops there and to Afghanistan have made it inevitable Australia will be attacked.