It's not yet clear how thieves are picking out homes of grieving families and ransacking them.
"(Families) are already going through so much and to have this happen to them is so troubling," said Curt Schildknecht, director of Schildknecht Funeral Home in O'Fallon.
Schildknecht said he received a call from the O'Fallon Police Department, warning him about the rash of break-ins happening in Belleville and Fairview Heights since last week. He said there haven't been any reports of thieves targeting O'Fallon, but added that the funeral service industry is taking this crime seriously and warning the communities they serve.
"We've advised all of our families to be very vigilant," he said. "To make sure that they have their security systems on and to advise their neighbors and to make sure they have someone staying at their homes."
One Fairview Heights family told FOX 2 over the phone Wednesday that earlier this month, someone broke into their house while they were away for their father's funeral.
They said the thieves not only trashed their home but also stole his Purple Heart.
"Who would traffic in a Purple Heart?" said Al Colvin, Illinois Patriot Guard Riders.
"I'm at a loss for words, I just can't conceive with anybody doing this. Our whole purpose is to show respect for the family, for the veterans, and to have somebody do what's being done, and I just don't grasp it."
FOX 2 made several attempts to reach out to the Belleville and Fairview Heights police departments to get some more information about their investigation into these crimes, but our calls were not returned.