Australian counter-terrorism officers have raided several homes after an investigation revealed that Islamic extremists were planning attacks in Sydney and Melbourne.
Police officials say security forces conducted raids Wednesday in the two cities. They gave no other details.
Australian media reports said police raided four houses in Melbourne and two in Sydney after the government's spy agency uncovered a plot to attack the famed Sydney Opera House and Harbor Bridge.
The reports said six people were detained for questioning.
Australia has had no major terrorist attacks on its soil, but 88 Australians were among the 202 victims of the Bali bombings in Indonesia in 2002. Militant groups have also vilified Australia for its support of the U.S.-led invasion in Iraq.
Some information for this report provided by AP and AFP.