DALLAS — Police have warned residents to "remain vigilant" after a series of robberies have been reported on the Dallas Katy Trail.

According to police, there have been four robberies reported. In each case, victims said two to three males under the age of 25 approached them on the trail and took their personal property, including cell phones, before fleeing the scene.

Dallas police said the offenses occurred between the time of 8 p.m. and 10 p.m. on Oct. 21, 25 and 29 and Nov. 7.

At least 5 victims have been targeted, and not all of them are women.

"The Dallas Police Department encourages citizens to be aware of their surroundings when walking or exercising alone," read a statement from police. "Remember, there is safety in numbers. If at all possible, avoid or use extra caution in when walking or running at night or in dark areas."

Tom McKay, who has lived in Dallas for 10 years, runs on the trail frequently and was ambushed by the thieves on Tuesday night.

"I was up around the American Airlines Center, and some guys jumped out from a seating area," McKay said. "The first guy had a knife, and there was three of them total. They all surrounded me and I had to give them my stuff."

"It was pretty terrifying," he said. "I've heard of it happening, but I never thought it would happen to me. It's definitely not what you're thinking about when you're out trying to go for a run."

Authorities have also encouraged residents to call 911 if they see anything suspicious on the trail.