It happened just before 7pm on FM 2920 at Falvel, about three miles west of Interstate 45 near Spring.
The accident involved three vehicles -- the injured deputy's cruiser, a Cypress-Creek EMS ambulance and a Nissan.
According to investigators, the ambulance was running with lights and sirens on as it tried to turn onto Tomball Parkway. A woman driving the Nissan didn't see the ambulance and hit it, along with the deputy's patrol vehicle, which was waiting at the light.
Officials said the deputy was transported to Tomball Regional Hospital. The woman in the Nissan was trapped in the vehicle and had to be rescued. She was taken to Woodlands Memorial Hospital.
Their injuries and conditions were not immediately released.
The ambulance was carrying a cardiac patient at the time of the collision who was subsequently transported to Tomball Regional Hospital. There is no word on that person's condition.
Please stay with Eyewitness News and abc13.com for updates.
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