Ottawa police are on the hunt for several men wanted in two separate taxi robberies.

Police released photos of the men on Thursday. Both robberies involved three male suspects.

Police say a group of three men caught a taxi on Mark Avenue on March 11. When they arrived at their destination, police say the man riding in the front seat apparently used a rock as a weapon, threatening the taxi driver and demanding money. The men got away with cash, and fled on foot.

Earlier this winter, police say a taxi driver was also robbed and assaulted by a group of three males just before midnight on Jan. 13. Police say their investigation reveals the suspects took a taxi from Gatineau to Ottawa prior to the robbery.

Drivers concerned

Although Ottawa taxis are required to have surveillance cameras, drivers say recent robberies have them concerned for their safety.

"The Ottawa police have to shove this up as a big priority because we get a lot of tough looking characters at night," said taxi driver Leo Pasco.

Pasco believes those in his profession are extremely vulnerable. He is also a victim of robbery.

"He grabbed me by the back of the neck, a head-lock, so to speak, and said: ‘Give me your money.' I certainly struggled," Pasco recalled.

Do cameras work?

The head of Ottawa's robbery unit acknowledges surveillance cameras won't stop all robberies, but they do help.

Ottawa Police Staff-Sgt. Don Sweet said installing a security camera won't stop those motivated to commit a crime, but it does help police identify suspects wanted for the offence. Cameras can also act as a deterrent, he added.

No data has been collected to determine if cameras have helped reduce the number of incidents targeting taxi drivers in the capital.

"Anecdotally, my feeling is that the number of robberies and assaults of the drivers has gone down significantly since the cameras were put into the taxis," said Linda Anderson, Ottawa's chief bylaw officer.

Still, some taxi drivers say a camera doesn't offer enough protection.

"Even though we have a camera, you know, if something happens to you by the time you get help or something, it's already done," one driver told CTV Ottawa.

Installing a shield

City staff says if drivers want more safety, they have the option of installing shields to separate them from their passengers. However, those shields would have to be purchased at their own expense, and may also require purchasing another camera.

"If the driver at this point wants to put a shield in, he may be in a position where he has to buy another camera to make sure he's capturing all the seats," said Anderson.

Anyone with information about these or any other robberies is asked to contact Ottawa police at 613-236-1222, ext. 5110 or Crime Stoppers at 613-233-TIPS.

With a report from CTV Ottawa's John Hua