Police are calling for "extra vigilance" after three swarmings in two days along the same south Ottawa pathway.

On Aug. 10 at around 9:30 p.m., a woman was walking along a pathway connecting Albion Road and Lorry Greenberg Drive when a male suspect who had been walking behind her demanded her backpack, the Ottawa Police Service said in a release Tuesday.

A second suspect then approached, brandishing a knife. The pair made off with a small quantity of cash, police said.

Bandana-wearing suspects

The next day, at around the same time, a woman was jogging along the path near Albion Drive when she came upon three males in bandanas, one of who was armed with a knife and a second who may have had a handgun, said police.

The jogger gave the suspects her cell phone, said police, after which they fled towards Cahill Drive.

In a third incident that happened "a short time before or after" the robbery of the jogger, a couple were walking along the pathway when three male suspects — also wearing bandanas — jumped out of some hedges, police said.

The suspects told the couple they needed money for their sick family member, and that no one would be hurt. When the couple said they didn't have any money, the suspects demanded the woman's necklace, said police.

This pathway is bordered by trees and bushes, and lower lighting levels provide adequate conditions for suspects to conceal themselves once [it's] dark. - Ottawa Police Service

Much like the previous robbery, one of the suspects was spotted with a knife while the other was seen carrying a handgun, police said.

The suspects are believed to be between 15 and 20 years old, either black or of Middle Eastern descent, with slim builds and of different heights, said police.

"This pathway is bordered by trees and bushes, and lower lighting levels provide adequate conditions for suspects to conceal themselves once [it's] dark," police said in their statement. "Extra vigilance is warranted as these investigations progress."

Anyone with information can call the Ottawa Police Service's robbery unit at 613-236-1222, ext. 5116. or Crime Stoppers toll-free at 1-800-222-8477 (TIPS).

No one was injured in any of the robberies.