EDISON - Police are investigating whether a string of armed robberies targeting pizza delivery workers are connected.

Authorities say the latest robbery happened Sunday night in Edison. They say Mike McCall was making a delivery for Edison Pizza when three men came from the side of the house. They surrounded him and put a gun to his head.

McCall says the men took $200, his keys and the pizzas.

Similar robberies have happened recently in South Brunswick, Franklin, New Brunswick and South River.