In a four-day period, 11 people died from probable drug overdoses in Milwaukee County.

"It's still a problem," said Sara Schreiber, who supervises the toxicology lab at the Milwaukee County medical examiner's office.

The office routinely released information about drug-related deaths, and Schreiber said she does not want people to begin to get used to, or worse ignore, that information and the scope of the drug epidemic.

"It took 11 people's lives in four days," she said Wednesday. "There's very potent drugs out there."

The office is on pace to record 426 drug-related deaths this year — a nearly 25% increase from the 343 deaths last year.

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Toxicology tests are pending in the recent cases and it's unclear if there is a common link to the drugs in each death, she said.

"It may be new substances, " Schreiber said. "It may be something we've been detecting for a while maybe with the potency changed a little bit, or maybe we just have new individuals who came in contact with it."

Of the 11 people who died from Friday through Monday, nine were men. Eight died at home. Ten died in the city of Milwaukee. One person died in Whitefish Bay. The median age was 40.

Two were visiting Milwaukee for a softball tournament. Jason S. Bunbury, 42, and Patryk M. Winiarski, 28, traveled from Ontario, Canada, and checked into the Potawatomi Hotel on Friday.

They were discovered deceased by housekeeping staff about 9:30 a.m. Monday.

Police found white powder and a rolled up bill on the top of a dresser. The powder was identified as fentanyl, a powerful opioid, in a preliminary test, according to medical examiner's reports.

On Monday night, a 16-year-old boy from Nashotah was found inside a car parked near N. 41st St. and W. Kaul Ave.

"We don't see that very often," said Karen Domagalski, operations manager at the medical examiner's office.

The office has seen an uptick of baby deaths related to drugs this year, but it is rare for a younger teen, she added.

"Everyone thinks it's the high school population," she said. "But it's about seven years since we've seen an overdose of a person this young who wasn't an infant."