Somebody has been dropping hot dogs with a poisonous substance inside, which has made dogs sick in a western Wisconsin town, police announced, urging people to be on the lookout for a possible suspect.

Evidence showed that person was cutting up the hot dogs, adding an unknown substance, then wrapping up the food with dental floss before tossing it in people's yards in Lake Hallie. Police got a series of phone calls about the crimes, Fox 9 reported.

EMAILS SHOW MISSING TENNESSEE TEACHER, STUDENT HAD 'ROMANTIC INTEREST,' OFFICIALS SAY

"If you happen to see more of this type of activity, please DO NOT let your animals ingest it and report it immediately," officers wrote in a Facebook post Friday.

Police also released a couple of blurry photos of the possible suspect, taken from a trail camera.

It's not clear exactly how many dogs have become sick.

Lake Hallie is a 90-minute drive east of Minneapolis.

Click for more from Fox 9.

The Associated Press contributed to this report.