KITCHENER -- An American trucker had a rude awakening when a rock was thrown through his side window, according to Guelph police.

Officials received reports of the incident from the Michigan resident just after 2 a.m. on Thursday.

He told police he was asleep inside his pickup truck when someone smashed his window and woke up to a male trying to climb into the cab.

The driver reportedly yelled and scared him off.

Police say the male grabbed a clipboard and cash off the seat, but the property was recovered.

Officers were unable to find the man in the area. He is described as wearing a yellow hoodie with an emblem on it.

The investigation is ongoing. Anyone with information is asked to contact Guelph Police Service.