MADISON, Wis. - An Illinois woman has been declared brain-dead after being shot during a random drive-by shooting along a Wisconsin interstate while travelling home with her husband and children, a coroner said Tuesday.

Tracy Czaczkowski, who was shot Sunday, was declared brain-dead early Monday morning and is being kept on life support only to preserve her organs for donation, said Greg Hahn, the coroner in Wisconsin's Sauk County, where the shooting took place. Hahn said her condition is irreversible and that it's accurate to say she is dead.

The U.S. Drug Enforcement Administration released a statement earlier Tuesday saying Czaczkowski had died. Her husband works for the DEA, but investigators believe the shooting was random and that the suspect had killed another person just hours earlier in suburban Milwaukee.

"Tracy was a loving wife of 15 years, a mother of two tender age children, daughter and good friend to all," the DEA statement said.

The family was returning to their home in Buffalo Grove, a Chicago suburb, after spending the weekend in the resort city of Wisconsin Dells when they passed a Chevrolet Blazer on Interstate 90/94. The Blazer's driver opened fire on their BMW sedan, hitting Czaczkowski in the neck, according to investigators. Police stopped the Blazer with a spike strip and shot the driver after he emerged with a gun.

The Dane County Sheriff's Office identified the suspect Tuesday as 20-year-old Zachary T. Hays of West Allis, a Milwaukee suburb, and said two of his brothers also were in the Blazer. No charges have been filed against Hays, and he remained hospitalized at the University of Wisconsin Hospital on Tuesday. His condition hasn't been released.

Investigators believe Hays killed 42-year-old Gabriel Sanchez in West Allis hours before the interstate shooting. Authorities have said responding officers found Sanchez fatally shot when responding to a report around 7 a.m. of a man forcing his way into a pair of apartments. At the time, police said Hays had also threatened members of a local church.

Hays has not been formally charged in either Sanchez's or Czaczkowski's deaths. Phone calls to numbers publicly listed for Hays' family were either disconnected or rang unanswered, and it wasn't immediately clear whether he had an attorney.

Court records show that Hays was found guilty of battery and receiving stolen property in Milwaukee in 2013. He was ordered to serve two years' probation. His defence attorney in the case, Bridget Krause, said she didn't remember details about the case.

One of Hays' brothers who was in the Blazer on Sunday, 30-year-old Jeremy Hays, was being held Tuesday on suspicion of being a felon in possession of a firearm. He has two felonies on his record: for a burglary in 2005, and for escaping custody in 2006, both in Milwaukee.

The sheriff's office said it opted not to identify the other brother who was in the Blazer because of his "cognitive disability." Sheriff's office spokeswoman Elise Schaffer said investigators are trying to get him back to his group home setting as soon as possible.

___

This story has been rewritten to clarify that the coroner says Tracy Czaczkowski was declared brain dead early Monday morning and is still on life support only to preserve her organs for donation.

News from © The Associated Press, 2016