Police are investigating the circumstances surrounding a home invasion near Lake Macquarie this morning.

About 10am (Thursday 10 December 2015) a woman knocked on the front door of a home in Fourth Street, Seahampton, and spoke to the 70-year-old occupant.

During the conversation a man appeared from behind the woman armed with a shortened firearm.

The pair forced their way into the home and assaulted the occupant with a hammer before stealing a large amount of cash, and dried cannabis.

The occupant managed to contact emergency services who attended the home.

A crime scene was established and the man was taken to John Hunter Hospital suffering what is considered to be non-life threatening injuries.

Police believe this was a targeted attack.