"Security has been tightened at Australian airports after police foiled 'Islamic-inspired' plans for a bomb attack on an aircraft during counter-terrorism raids in which four men were arrested, the Australian Federal Police (AFP) said on Sunday...
'In recent days, law enforcement has become aware of information that suggested some people in Sydney were planning to commit a terrorist act using an improvised device,' AFP commissioner Andrew Colvin said during a press conference with Prime Minister Malcolm Turnbull on Sunday.
'We do believe it is Islamic-inspired terrorism. Exactly what is behind this is something that we will need to investigate fully.'...
Australia, a close ally of the United States, has been on heightened alert for attacks by home-grown militants returning from fighting in the Middle East, or their supporters, since 2014.
Authorities say they have thwarted a number of potential attacks since then but there have been several 'lone wolf' assaults, including a cafe siege in Sydney that left two hostages and the gunman dead.
About 100 people have left Australia for Syria to fight alongside organizations such as Islamic State, Australia's immigration minister said last month."