(WTTW News)

Ninety percent of the opioid overdose deaths involved fentanyl, according to Cook County’s Medical Examiner’s Office. 

A memorial for Jean Carlos Martinez Rivero sits on the ground next to candles during a vigil for the 5-year-old who died over the weekend at the Lower West Side shelter, Wednesday, Dec. 20, 2023, in Chicago. (Armando L. Sanchez / Chicago Tribune via AP)

Jean Carlos Martinez was a resident at a warehouse retrofitted as a shelter in Chicago’s Pilsen neighborhood when he suffered a medical emergency, the city said. He was pronounced dead shortly after arriving at a hospital Sunday afternoon.

Jail personnel go through stacks of letters and books in the mail room at Cook County Jail on Oct. 12. All mail coming into the jail has faced greater screening methods since the paper restriction began in April. (Cary Robbins / DePaul)

Since the beginning of 2023, Cook County Jail administration has reported 16 deaths in custody, with five attributed to overdoses, according to Cook County Medical Examiner records. To address the uptick in overdose deaths, jail leadership took unprecedented measures, including what some called a facility-wide paper ban. 

Sergio Brown is shown here helping to coach a team of local school children on July 15, 2015, in London, England. (Dan Mullan / Getty Images via CNN)

Authorities discovered the body of 73-year-old Myrtle Brown on Saturday after relatives alerted police they’d been unable to find or contact her or her son, the Maywood Police Department said in a news release.

(WTTW News)

There were 103 overdose deaths attributable to fentanyl in Cook County in 2015. That number shot up to a record 1,825 in 2022, according to statistics from the Cook County Medical Examiner’s Office. That accounts for more than 90% of all opioid-related deaths in the county.

Dr. Rahul Gupta, the director of the White House Office of National Drug Control Policy, walks outside of the White House, Nov. 18, 2021, in Washington. (AP Photo / Alex Brandon, File)

The Office of National Drug Control Policy announced the designation Wednesday, the first time the office has used it since the category for fast-growing drug dangers was created in 2019.

A naloxone kit from the Chicago Recovery Alliance is pictured in a file photo. The organization is among those working to deal with an influx in xylazine. (Kristen Thometz / Chicago Tonight)

The veterinary drug was connected to a rising death toll in Cook County and across the state. The new restrictions aim to prevent the drug from entering the U.S. market for illicit purposes.

A naloxone kit from the Chicago Recovery Alliance is pictured in a file photo. The organization is among those working to deal with an influx in xylazine. (Kristen Thometz / Chicago Tonight)

Data from the Cook County Medical Examiner’s Office shows 146 opioid-related deaths last year where xylazine was listed as a primary cause, marking a 16.8% increase from 2021. Local harm reduction organizations have also seen an uptick in its use.

Naloxone reverses an opioid overdose if administered in time. (WTTW News)

The key culprit appears to be the widespread availability of the powerful synthetic opioid fentanyl.

(ValynPi14 / Pixabay)

More than 1,000 homicides have been recorded in Cook County so far this year. In the suburbs, Harvey has seen the highest total of homicides with 30.

(WTTW News)

The Cook County Medical Examiner’s Office confirmed its 1,000th homicide of the year over the Thanksgiving holiday weekend, though that total has since grown to at least 1,009, per county officials.

The Chicago Police Department, with assistance from the Cook County Sheriff's Office, has released a composite sketch of the dismembered child found in the Garfield Park lagoon last weekend, and authorities are asking residents for assistance in identifying the remains.