Ottawa police are asking jewelry store owners to be vigilant after two smash-and-grab robberies that investigators believe are related. 

The first robbery took place Wednesday, Dec. 23, police said in a media release issued Tuesday.

Three young men walked into a jewelry store at Carlingwood Mall off Carling Avenue just before 6:20 p.m. and smashed "a number of display cases" before fleeing the scene with jewelry.

Police won't say how much jewelry was taken.

Then, on Jan. 4, a similar robbery took place in a jewelry store at Billings Bridge Shopping Centre, this time involving four young men.

One of the men used a sledgehammer to break display cases while the others grabbed an undisclosed quantity of jewelry. The group then fled into the mall.

There were no injuries.

Jewelry store owners are being asked to report any suspicious activity to police.

Anyone with information about the robberies is asked to call the Ottawa police robbery unit at 613-236-1222, ext. 5116. Anonymous tips can be submitted by calling Crime Stoppers toll-free at 1-800-222-8477(TIPS).