5:30pm: Police have now stormed a unit block at the centre of an operation in West Wollongong on Tuesday.
At this stage it's not known whether anyone has been arrested. However, it's believed the police will address the media soon.
4:50pm: A siege currently underway at a unit block in West Wollongong is understood to be over outstanding arrest warrants.
A NSW Police spokeswoman told the Mercury that officers attended a home earlier today to arrest a man for outstanding warrants for serious offences. As a result a police operation is now underway, she said.
Dozens of police - including heavily armed tactical officers - can be seen surrounding the units near the corner of Thames Street and the Princes Highway.
A tactical team have so far broken down the front door and entered inside, after several hours trying to negotiate with the occupant.
Traffic diversions are in place and Thames Street has been closed to the public between the Princes Highway and The Mall.
4:38pm: Witnesses say armed police in tactical gear have now broken down the front door to one of the units.
4:10pm: NSW Police have issued a statement and urged the public to avoid the area with an exclusion zone now set up.
The police operation is underway at a unit block on the western side of the Princes Highway, which is West Wollongong - opposite the Hellenic Club.
"Police urge commuters to avoid the area," NSW Police said.
"Traffic diversions are in place and Thames Street has been closed to the public between the Princes Highway and The Mall."
Earlier: A police operation is underway in Figtree after reports of a siege.
Police rescue squad officers and general duties crews rushed to the Princes Highway area near the Wollongong Hellenic Club around midday.
Police negotiators are now on scene.
The operation is centred on a block of units opposite the club.
More to come..