Ottawa police have laid charges following the robberies of several marijuana dispensaries earlier this fall.

Seven robberies have occurred at dispensaries so far this year, police said in a media release issued Friday.

Nov. 16: A dispensary was robbed on Antares Drive.

A dispensary was robbed on Antares Drive. Nov. 11: Two men robbed the Sylk Medy dispensary on Gladstone Avenue.

Two men robbed the Sylk Medy dispensary on Gladstone Avenue. Nov. 5: Three men with a gun robbed a dispensary on Iber Road while a fourth suspect waited outside.

Three men with a gun robbed a dispensary on Iber Road while a fourth suspect waited outside. Oct. 27: Four men with one handgun robbed a dispensary on Bank Street in South Keys.

Four men with one handgun robbed a dispensary on Bank Street in South Keys. Oct. 26: Three men with a handgun robbed the Ottawa Cannabis Dispensary on Laperriere Avenue.

Three men with a handgun robbed the Ottawa Cannabis Dispensary on Laperriere Avenue. Oct. 23: Two men — one carrying a gun and the other a knife — robbed CannaGreen on St. Joseph Boulevard.

Two men — one carrying a gun and the other a knife — robbed CannaGreen on St. Joseph Boulevard. Sept. 6: Two men with a gun assaulted a worker during a robbery at WeeMedical Dispensary on Rideau Street.

Four men — two 23-year-olds from Ottawa and Gatineau, a 22-year-old from Vars, Ont., and a 25-year-old from Ottawa — are facing charges in connection to three most recent robberies, on Nov. 5, 11, and 16.

Staff Sgt. Mike Haarbosch of the Ottawa police robbery unit said investigators are looking into the possibility the suspects are linked to other dispensary robberies.

Court appearance Friday

The suspects were expected to appear in court on Friday. The charges against them include disguise with intent, possession of property obtained by crime, robbery with a firearm and conspiracy to commit an indictable offence.

The arrests took place Wednesday after police stopped a vehicle in the area of Bank Street and Heron Road. Two of the four men inside fled.

One was arrested nearby, and the second was tracked down with the help of dogs, police said. He suffered a minor injury and was treated in hospital.

Police searched the area where the pursuit took place on Thursday and found a loaded handgun. Additional charges against the four men are expected, police said.

Staff sometimes hesitant to cooperate

The federal government has promised to introduce legislation to legalize marijuana by the spring of 2017 but possession, production and trafficking of marijuana remains illegal — including operating pot dispensaries.

Haarbosch said the status of pot dispensaries has in some cases presented challenges.

"From time to time we get a little bit of hesitation in the employees cooperating with police in the form of providing statements, and we have also seen some hesitation in providing copies to police of surveillance footage of the robberies. We seem to be working past that," he said.

Haarbosch said that despite some "initial hesitation," robberies at dispensaries are now being reported to police.

"I'm not aware ... that there have been dispensaries robbed that have not been reported to police," he said.

"These are violent crimes committed not necessarily against the owners of the business. I mean, there's a financial loss there, certainly, but these are crimes that the employees have been victimized by."