A funny thing happened to some Bolingbrook Public Works employees while removing some garage sale signs from along Janes Avenue on Aug. 2.

They found a package of explosive materials sitting on a curb.

Wait, it gets even better.

After about six hours of investigation, which included evacuating some nearby residents from their homes and the use of a tactical robot supplied by the DuPage County Sheriff’s Office Hazardous Device Unit, it was discovered the explosive materials belonged to the DuPage County Sheriff’s Office Hazardous Device Unit, otherwise known as the Bomb Squad.

“It’s obviously a little bit embarrassing, and we are treating it very seriously,” said Chief Michael Blazek, head of the Law Enforcement Bureau of the DuPage County Sheriff’s Office.

“Fortunately, all of the individual explosive elements in the package were stable in nature, and all of the elements were accounted for and either recovered or rendered harmless,” said Blazek.

Blazek did not go into detail on the individual contents in the package other than to describe them as “conventional high explosive materials ... nothing improvised.”

The package apparently was part of a bomb-sniffing canine unit’s training session earlier that day at an unspecified location “in another county,” said Blazek.

“We are still conducting our own internal investigation to get to the bottom of how it came to be left on the ground, but it appears that the package may have fallen off of our unit’s vehicle as it was traversing  back to DuPage County, or it might have fallen out of the vehicle at that location,” Blazek said. “At this point we don’t know for sure.”

It all started about 1:30 p.m. when some Bolingbrook Public Works Department employees spotted a box of items on a curb at the northwest corner of the intersection of Janes Avenue and Anne Lane, near IKEA.

The employees contacted Bolingbrook police to report “suspicious items in the street,” said Lt. Chris Prochut of the Bolingbrook Police Department.

“Apparently the Public Works employees were out there taking down garage sale signs when one of them came across the package,” Prochut said.

According to Prochut, the first responding Bolingbrook officer observed what appeared to be an ammunition box that contained a yellow cylinder, some glass jars and some wires protruding from the box.

The officer immediately called for assistance, and the DuPage County Sheriff’s Office Hazardous Device Unit was called in.

Residents in nearby houses were evacuated, and others were told by authorities to remain inside their homes while technicians from the Bomb Squad investigated, Prochut said.

Janes Avenue was closed between Anne Lane and Kensington Way from 1:30 p.m. to 7:45 p.m. while traffic was rerouted to other local arterial streets.

A remote controlled tactical robot approached the package and eventually identified the materials as belonging to the DuPage County Sheriff’s Office Hazardous Device Unit from words on some of the materials inside the box, Prochut said.

By about 7:45 p.m. the materials were “rendered harmless” and the street reopened about 8 p.m., said Prochut.

Blazek said almost all of the materials in the training kit “were recovered” and did not have to be destroyed, although one chemical had to be diluted with diesel fuel and slowly burned to eliminate the threat.

“To burn the material took about 20 to 25 minutes,” Blazek said.

No one was injured in the incident.

Blazek said he did not know what, if any, disciplinary measures would be taken because of the incident.

“We aren’t real happy this happened and we are embarrassed by it, but the investigation eventually will give us the information we need,” Blazek said.

No timetable was given for completion of the investigation.