CHICAGO (CBS) — Several dogs out for Sunday walks with their owners in East Lakeview ended up writhing in pain.

As CBS 2’s Mike Puccinelli reported, an electrified manhole cover at the southeast corner of Halsted Street and Wellington Avenue was blamed for the incidents.

Police said the injuries to the dogs are not believed to be life-threatening, but they are still extremely disturbing for Chicago animal lovers.

At first glance the sawhorses covering the manhole don’t seem that unusual. But take a closer look at the yellow and red tape and it becomes a little disturbing.

The yellow tape reads, “Police line do not cross,” but the red tape says, “Caution: biohazard.”

“The dog was on the ground and was barking constantly and had blood in his mouth,” said Sarah Padilla of Foursided Cards and Gifts, just a stone’s throw to the east at 2958 N. Clark St. “The owners were freaking out, of course.”

They were freaking, because witnesses say the manhole cover ended up being really hazardous for several canines Sunday.

“It happened to two more dogs, unfortunately,” Padilla said.

The dogs suffered electric shocks when they stepped on the manhole cover.

“It was a manhole cover at the corner of Halsted and Wellington that was sending up electrical currents and shocking the dog,” Padilla said.

She said at least one of the dogs had a seizure.

“I’m not an expert, but I believe the blood was from the dog biting its own tongue,” Padilla said.

A witness said a fourth dog was seen lying on the electrified manhole cover for 20 minutes. That dog was yelping and whimpering in pain the entire time and defecated on itself, the witness said.

“I saw cops here all day long checking out what was going on,” a man at the scene added.

It’s a shocking issue that’s been going on for years.

In 2015, dog owner Thomas “Shoebocks” McGee reported that his dog was shocked after stepping on a wet light pole in Humboldt Park.

And just a few months ago, Kathleen Brown said her dog was nearly electrocuted while walking over a manhole cover at Jackson Boulevard and Green Street in Greektown.

Brown said her dog, Penelope, was shrieking in pain.

“I’ve never heard her make that noise before,” Brown told CBS 2’s Eric Cox on Sept. 1, 2019.

In response to the incidents Sunday at Halsted and Wellington, Animal Care and Control and the Chicago Department of Transportation both sent out teams.

“Obviously, as a dog owner in this area, it’s super scary to not know that and essentially have that hazard going on,” said dog owner Morgan Pruckner. “It could have been anybody’s dog that that happened too.”

Now, area dog owners just want the city to figure out what happened and why – so they don’t have to start carrying their dogs instead of walking them around town.

“Honestly, my main hope is that the dogs are OK,” McGee said.

ComEd said they got a call from Chicago Police regarding the manhole. They dispatched a crew and determined the manhole does not contain ComEd equipment.

Mike Puccinelli