MELBOURNE, Australia — Police in Australia foiled terrorist plans for commando-style suicide attacks on at least one army base, arresting four men Tuesday with suspected links to a Somali Islamist group, senior officers said.
Prime Minister Kevin Rudd said the plot was a "sober reminder" that Australia is still under threat from extremist groups enraged that the country sent troops to join the U.S.-led military campaigns in Afghanistan and Iraq.
Some 400 officers from state and national security services took part in 19 pre-dawn raids on properties in Melbourne, Australia's second-largest city, and arrested four men, all Australian citizens ranging in age from 22 to 26, police said.
Several others were being questioned Tuesday, police said.
Australian Federal Police Acting Commissioner Tony Negus said the raids followed a seven-month surveillance operation of a group of people allegedly linked to al-Shabaab, an al-Qaida-linked Somali extremist organization that has been fighting to overthrow Somalia's transitional government.
The cell's plans included sending members armed with automatic weapons into military bases in Australia, including Holsworthy Barracks on the outskirts of Sydney, Negus said.
"The men's intention was to actually go into the army barracks and to kill as many soldiers as they could before they themselves were killed," Negus said. "This operation has disrupted an alleged terrorist attack that could have claimed many lives."
The suspects were due to appear in court later Tuesday. Rudd said they would face charges under federal laws of planning or preparing a terrorist act.
"As the Australian government has said consistently, there is an enduring threat from terrorism at home here in Australia, as well as overseas," Rudd told reporters in the northern city of Cairns. "This is a sober reminder that the threat of terrorism to Australia continues."
He said he had been advised that "events today do not at this time warrant any change to our national counterterrorism level, which remains at medium" — the same security-warning rating that has been in place in Australia since the Sept. 11, 2001, terrorist attacks in the United States.
Australia has not suffered a terrorist attack on its home soil since the Sept. 11 attacks in the U.S. raised security-threat levels worldwide. But dozens of Australians have died in terrorist attacks overseas, mostly in Indonesia, including the 2002 bombings in Bali that targeted nightclubs frequented by Australians and other foreigners.
Homegrown terrorist plots have also been relatively few. Seven men were imprisoned in the past year for involvement in a nascent plot to attack major sporting events in Australia in what prosecutors said was the country's largest terrorist conspiracy.
After the Sept. 11 attacks, Australia introduced tough new counterterrorism laws that grant police and security agencies strong surveillance and detention powers, and stiffen prison sentences for convicted terrorists. Australia does not have the death penalty.
Al-Shabaab, which conducts frequent attacks in Somalia, is seeking to overthrow Somalia's Western-backed government and establish an Islamic state. The group has claimed responsibility for several high-profile bombings and shootings in the Somali capital of Mogadishu targeting Ethiopian troops and Somali government officials. It has also killed journalists and international aid workers.
The U.S. State Department's annual terrorism report in April said al-Shabaab was providing a safe haven to al-Qaida "elements" wanted for the 1998 bombings of the U.S. embassies in Kenya and Tanzania. The two groups have long been suspected of working together, but they have not announced a formal alliance. Al-Qaida has operations in north Africa, Yemen and Iraq.