Teen charged over alleged attempt to rob two plain-clothes police near Ballarat

A 16-year-old boy has been charged following an attempted armed robbery of plain-clothes police in an unmarked car near the Victorian city of Ballarat.

The officers were patrolling in a state forest in Canadian when they were boxed in by two other cars about 11am on Wednesday, police said.

A male from one of the cars approached the officers, then allegedly pulled out a knife and demanded cash from them.

The 16-year-old was arrested after a brief struggle, but his three accomplices fled in their cars.

The officers, both from the uniform section of Ballarat police, were unharmed.

The teen has been charged with armed robbery, attempted armed robbery and other offences and will appear in a children's court tomorrow.

Police are still searching for a red Opel sedan with stolen registration plates that was last seen near Delacombe and a gold Peugeot sedan carrying two men that was last seen in Ballarat.

With AAP