HOUSTON -- I-45 North was shut down after a crash involving an ambulance early Monday.

All northbound lanes were blocked at Parker Drive as of 9:30 a.m., but the freeway has since reopened.

Views from Houston TranStar showed an ambulance is on its side, but the Houston Fire Department says no patient was aboard.

The ambulance was upright and cleared out of the way shortly before 10 a.m.

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