St. Charles Parish Sheriff Greg Champagne issued what he called a heroin danger alert after he said two men in their mid-30s died Tuesday in a residence on Paul Fredrick Street in Luling after injecting heroin.

Champagne raised the possibility there may be a “bad batch” of heroin tainted with a substance like fentanyl, and he asked residents to warn drug users.

“This is the first time I have ever seen a double death overdose situation such as what we discovered today,” Champagne said Tuesday. “Autopsies are pending, but I felt compelled to put this warning out tonight since we are fairly confident of what happened.”

An official determination of the men’s cause of death has not been made, and authorities have not concluded whether the heroin the men used was tainted with any other substances.