A truck left running on this Surrey street Monday was stolen while an infant slept inside. A truck left running on this Surrey street Monday was stolen while an infant slept inside. (CBC)

A Surrey, B.C., couple had an hour of terror after their truck was stolen with their six-week-old baby inside.

The truck was found a few blocks away with the unharmed infant still inside Monday night.

Police speculate the thief saw he'd taken more than he bargained for when he made off with the vehicle, which had been left running.

"Perhaps the individual who stole it realized what was in the truck," said Surrey RCMP spokesman Const. Peter Neilly.

The truck was left in a visible spot near 152 Street and 26 Avenue, Neilly said.

Forensic investigators will be looking at the truck for possible clues while other officers seek possible witnesses.

Neilly said Surrey has a bylaw prohibiting anyone from leaving an unattended vehicle running.

Police said investigators would also look at how long the infant had been left in the truck.

The child's mother was quoted as saying she had been dropping mail off at her parents' home and had left the truck for only a minute before she noticed that it had been stolen.