York Regional Police are investigating after four people were injured during a bank robbery in Markham Wednesday night.

Emergency crews were called to an RBC bank in the area of 16th Avenue and Markham Road just after 8 p.m.

Police said two were stabbed and two others suffered head injuries. All four are employees at the bank.

One of the stabbing victims was taken to a trauma centre in serious condition while the others were transported to a local hospital in non-life-threatening condition.

Police said three suspects, who were possibly armed with knives and gun, fled the scene on foot.

With the help of the K9 unit, the suspects were later located and taken into custody, police said.

The suspects are all believed to be under the age of 17.

There will be a large police presence in the area for the next few hours as the search for evidence continues.