Life-threatening injuries were reported in a crash Tuesday in Warwick Township.
Lambton OPP said just before 1 p.m., two vehicles collided on Egremont Road, sending one person to hospital.
Middlesex OPP, Warwick Township Fire and Rescue, and Lambton EMS also responded.
A section of Egremont Road between Wisbeach Road and Sexton Road was closed for over 10 hours while police conducted their investigation.
The West Region Traffic Incident Management and Enforcement (TIME) Team is assisting in the investigation.
Anyone with information is urged to call OPP at 1-888-310-1122, or Sarnia-Lambton Crime Stoppers at 1-800-222-TIPS (8477) or online at www.p3tips.com.