(CBS) – Bicyclists have been knocked off their bikes and in at least one case robbed at gunpoint along Chicago’s 606 Trail, an elevated recreational path, Chicago police say.

The incidents occurred July 2 and on Saturday and Sunday in the early morning hours, Chicago police said in a community alert issued Sunday.

READ MORE: Illinois COVID-19: State Reports 1,248 More Cases, 24 Additional Deaths

In the first two incidents, in the 3300 and 3500 blocks of West Bloomindale, suspects knocked victims from their bikes, and the riders were injured.

In the latest incident — 4:30 a.m. Sunday at 1850 N. Ridgeway — a bicyclist was robbed at gunpoint and beaten. The offenders demanded the rider’s belongings, police said.

READ MORE: Two Chicago Police Officers Shot On South Lawndale Released From Hospital

The alert asks people who use the 606 Trail to be vigilant and report information to police.

The 606 Trail is a converted former rail bed that goes through Northwest Side neighborhoods such as Bucktown and Humboldt Park.

MORE NEWS: 13-Year-Old Boy Riding Bicycle Critically Wounded In Shooting