ROMULUS (WWJ) – Rush hour was anything but that after a U.S. Postal Service mail truck caught fire Thursday morning along I-94 westbound near Detroit Metro Airport.

It happened just before the commute began and cleanup continued past 9 a.m. following the incident near Haggerty Road in Romulus. WWJ’s John Bailey reported traffic was backed up and crawling for three miles west of the airport, through the I-275 interchange, with motorists only getting by in the left lane.

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A crew from the Romulus Fire Department extinguished the blaze.

Sabrina Todd, Communications Spokesperson for the Greater Michigan District Postal Service, said no one was injured in the fire —but there was mail on board that may not have made it.

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Todd said USPS personnel were investigating the incident and she hoped to have more information available to the media and postal customers later in the day.

It was not immediately clear what caused the fire.

The scene has since cleared and traffic was moving on westbound I-94 by 10 a.m.

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For the latest from the roads, stay with WWJ Newsradio 950 during Traffic and Weather on the 8s, 24-hours a day. Check for recent incidents now on the CBS Detroit Traffic Page.