ROCKVILLE, Md. (AP) — An ambulance and a fire truck that collided in Montgomery County injured six people.

Montgomery County fire spokesman Peter Piringer says two of the people had serious injuries, but not life-threatening.

Piringer says the emergency vehicles had left separate stations to respond to a call about a hazardous materials situation in Rockville on Thursday when they collided.

Five people in the fire truck were treated and released from the hospital, while one person in the ambulance remained hospitalized with serious injuries.

The crash is under investigation.

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