Police in northwest suburban Arlington Heights are investigating a series of “creepy clown” sightings that happened last week amid a national wave of sightings and threats — largely unfounded — that has swept into the Chicago area.

Police did not specify the times of the sightings, but calls of people in clown masks were reported in the 1500 block of West Vine Street and at Westgate Park, 211 N. Reuter Drive, according to Arlington Heights police.

Someone else claimed to see a bicyclist wearing a clown mask at Northwest Highway and Dunton Avenue, and another claimed a male in a white jumpsuit — though not definitively a clown — was seen going into the woods at Carefree Park, 1231 S. Belmont Ave., police said.

Officers didn’t find anyone or anyone suspicious in responding to the calls, police said.

The clown craze has prompted warnings from police and school officials in Chicago and numerous suburbs.