CHICAGO (CBS) – Three students were struck by vehicles on separate days since school started last week in Round Lake.

Three different incidents occurred Aug. 22, 26 and 30 where a student was struck by a vehicle, WBBM’s Lisa Fielding reports.

READ MORE: 'It Sounded Like An Automatic Weapon': Video Captures Rapid Gunfire In River North Shooting That Left Two Injured

“Activity is normal, the busyness,” said Police Chief Michael Gillette. “But we have not had accidents like this before.”

One incident was a bicyclist, who used the crosswalk, but road into traffic when he did not have the right of way, police said. Another was a cross-country runner, who entered the roadway without looking and ran right into traffic.

READ MORE: Girl Kidnapped By Three Men In Ski Masks Near Austin High School

The students were taken to Advocate Condell Medical Center in Libertyville for precautionary reasons. Police said no one was seriously injured and no drivers were ticketed or considered at fault.

“We’d like drivers to pay attention to the school zones,” Gillette said. “Slow down; make sure they are not exceeding the school zone speed limit. At minimum, watch for the pedestrians. They are new going to school and they are not used to paying to that much traffic either.”

A traffic safety enforcement crackdown has started by Round Lake Police. Police are monitoring pedestrians and drivers at or near the signalized crossing where Cedar Lake Road intersects with Washington Street and Hart Road to the south near John T. Magee Middle School, Gillette said. Enforcement around those two intersections was stepped up Wednesday.

Officers plan to issue vehicular and pedestrian citations when appropriate.

MORE NEWS: Police Seeking 2 Men Who Carjacked Woman And Family Members During A Delivery in Ford Heights

Round Lake Police have issued at least nine tickets to students for failure to use the crosswalk so far.