Police lay 137 charges against 4 teens accused of physically assaulting victims in 'take-over' style robberies

Calgary police have laid 137 charges against four 16-year-old boys who investigators believe are responsible for a string of "violent, take-over style robberies" in the city.

Over a two-week period in November and December, police were called to eight robberies at pharmacies, convenience stores and vape shops for incidents involving handguns and violence.

Once inside each store, the robbers rushed behind counters and threatened employees with weapons before demandingcash, nicotine products and pharmaceutical drugs.

In most cases, staff members reported being punched, kicked and pistol whipped.

Level of violence 'disturbing' and 'traumatic': police

"The level of violence victims are experiencing during these robberies is disturbing and has had traumatic effects," said Staff Sgt. Kathy Graham with Calgary police.

"Watching footage of these robberies and assaults is shocking and our investigators have been working tirelessly to apprehend and charge those responsible."

All the people facing charges are 16-year-old boys who can not be named under the Youth Criminal Justice Act.

Their charges include robbery with a firearm, forcible confinement, disguise with intent to commit a crimeand possession of a dangerous weapon.

More arrests, charges expected

The investigation continues as police believe there are others involved.

"Additional arrests and charges are expected," said police in a statement.

They are asking for the public's help identifying three more suspects believed to be around 16 and 17 years old involved in a violent pharmacy robbery which took place on Nov. 18 at the Pharmasave on Martindale BoulevardN.E.

In that incident, four people stormed into the pharmacy and yelledat staff and customers to get on the ground.

One suspect was carrying a handgun and while demanding staff open the pharmaceutical drug safe, pistol whipped and kicked an employee.

Anyone with information is asked to call the non-emergency police line at 403-266-1234.

Anonymoustips can also be sharedthrough Crime Stoppers.