Tougher laws will strengthen crackdown

Halting the spread of extremist propaganda online seen as pressing issue, summit told

Australia will expand a crackdown on Islamist militant groups with more tough security legislation, the attorney general told a regional summit aimed at combating violent extremism on Friday.

The country is on high alert for attacks by radicalized Muslims, including homegrown militants returning from fighting in the Middle East. Australia has already raised its threat level to "high" and carried out a series of high-profile raids in cities.