Police and other emergency services attended a unit block in Northcliffe Drive about 2.30am on Friday, December 27, following reports a unit was on fire.

The blaze was extinguished and it was established the unit was not occupied at the time.

No-one was injured.

Strike Force Roxat, consisting of officers from Lake Illawarra Local Area Command, was formed to investigate.

Detectives are continuing investigations into the incident and have released a computer-generated image of a woman they would like to speak to.