WATERLOO, Ill. — A woman arrested in on drug charges in Waterloo died in the Monroe County Jail after receiving treatment at a hospital Tuesday.

Police said they pulled a U-Haul vehicle over for a traffic violation. During the stop, they arrested three people on drug-related charges.

During the booking process, police said a 40-year-old woman swallowed an "unknown substance". She was taken to Memorial Hospital in Belleville for treatment before being released back to police custody.

When she arrived at the jail, police discovered she was unconscious. Officers gave her CPR and called an ambulance. She was taken to Red Bud Regional Hospital where she was pronounced dead.

The Randolph County Coroner's Office is investigating the death.

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