An elderly man has been viciously attacked during a home invasion in front of two young children at a Mandurah property overnight.

Police said a man entered the Truarn Street home through the front door at around 9pm on Wednesday evening, and attacked the elderly man with an unidentified weapon.

Police are searching for the man accused of bashing the elderly victim. Credit:Andrew Quilty

The 83-year-old man was left with serious injuries, and it is understood an 11-year-old boy and a 12-year-old girl witnessed the attack.

The attacker left the house and headed towards Burley Street.