Chelmsford firefighters responded early Sunday morning to a rollover crash on I-495 in which one person was reportedly ejected.
The crash was reported about 3 a.m. on I-495 southbound at Woburn Street. The commander initially called for a medical helicopter, but an ambulance was used instead, according to an initial scanner report.
The person sustained serious injuries, according to the report.
Chelmsford Patch will update when more information is available.