Three Sydney men have been arrested over an alleged Islamic State-inspired plot to attack a variety of targets in Australia including embassies, police stations and court buildings.

Isaak el Matari, 20, and two other men aged 23 and 30, were arrested in counter-terror raids across Sydney’s south west and were taken to Bankstown police station.

Police targeted six addresses in Greenacre, Canada Bay, Toongabbie, Chester Hill and Ingleburn this morning.

Isaak el Matari, 20,was one of three men arrested today as part of the anti-terror raids. (Supplied)

Police allege the younger men were members of Islamic State and the plot - which was in the "early stages" of planning – was to target police stations, defence establishments, embassies, councils, courts and churches.

Speaking about the arrest of three men in Sydney today, Assistant Commissioner Ian McCartney Australian Federal Police said the joint raids were designed to keep Australia safe and showed there were still those in the community who "wished to do us harm".

The NSW Joint Counter Terrorism Team - which includes Australian Federal Police officers - conducted the raids following a 12-month investigation "targeting a group of people alleged to support the Islamic State terrorist organisation".

Police and detectives raided six homes this morning across Sydney as they disrupted a terror plot that police allege was aimed at police stations, courts and churches. (9News)

Ass Comm McCartney said the 20-year-old man from Greenacre had been monitored for the past 12 months since returning to Australia from Lebanon, where he had been deported after being jailed for planning to travel to Syria to join Islamic State.

The 23-year-old from Toongabbie was allegedly "prominent in the global online extremist community".

Police have also said they believe the men met on social media and shared an allegiance to Islamic State.

"We will say that they had a number of targets, including police stations, defence establishments, embassies and councils, courts and churches," Ass Comm McCartney said.

"I need to stress the priority of the work of the JCTT was to prevent this attack occurring and we were satisfied up until this morning when the arrest was made that this man had not moved to finalise his plans in relation to this terrorist attack.

"We will also allege this man had indicated he was willing to travel to Afghanistan to fight for Islamic State, and he made a number of preparations to do so.”

NSW Police at a home in Greenacre today as they executed a warrant. (AAP)

He said the men did not represent the Muslim faith, describing their actions as "criminal."

Home Affairs Minister Peter Dutton also acted swiftly today, announcing he will table new laws in parliament this week to stop people suspected of having terror links returning to Australia for two years.

“This threat has not diminished, it’s not going away, it remains current – particularly when we’ve got Australians overseas in a theatre of war being trained by ISIL or being inspired online and we want to deal with those people as best we can,” he told reporters today.

(9News)

Forensics teams today also worked to examine laptops, computers, mobile phones and tore up floor boards in the homes targeted in the raids in the search for evidence.

The 20-year-old is expected to be charged with preparing for a terrorist act and preparing to enter a foreign country for the purpose of engaging in hostile activities.

He could be jailed for life if found guilty.

The 23-year-old is expected to be charged with being a member of a terrorist organisation.

Police have spent the day gathering evidence from across the six properties after making three arrests. (9News)

Ahmed Tebya, 30, is believed to be an associate of the other men and is expected to be charged with obtaining financial benefit by deception through fraudulently claiming unemployment benefits. He too faces 10 years behind bars.

The AFP earlier released a statement saying there is no immediate threat to the safety of the community.

"The NSW Joint Counter Terrorism Team (JCTT) can confirm it is conducting operational activity in Sydney today," it said.

"There is no immediate threat to the safety of community as a result of this activity."

All three men are expected to appear before Parramatta Local Court today or tomorrow once charges have been laid.

Anyone with information about extremist activity or possible threats to the community is asked to call 1800 123 400.