Reward offered for info on Vic attack

Victoria Police have announced a reward of up to $350,000 following a violent home invasion where an elderly couple was tied up and assaulted last year.

Two men wearing balaclavas forced entry through a window at the Delburn home sometime between 2am and 6am on January 11, police say.

The elderly couple was asleep at the time and woke up to someone shining a torch in the bedroom.

An 80-year-old man suffered significant brain damage during the unprovoked attack and a 75-year-old woman suffered minor injuries during the ordeal.

"Someone out there knows who is responsible for this, and we are appealing for them to make contact with police," Detective Leading Senior Constable Paul Burns said on Monday.

A reward of up to $350,000 will be paid, at the discretion of the Chief Commissioner of Police, for information leading to the apprehension and subsequent conviction of the person or persons responsible for the assault of the elderly man.