A Delta plane dumped fuel for about an hour Saturday over Lake Michigan before it safely landed back at Detroit Metropolitan Airport after a warning light came on shortly after takeoff.

The light indicated there could be an open maintenance panel on the outside of the plane, according to the Detroit Free Press.

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The flight, which had 375 passengers, took off at 4:48 p.m. The light came on about 30 minutes into the flight.

"They landed safely without incident," Trebor Banstetter, a Delta spokesman, told the Detroit Free Press.

Maintenance crews were checked out the plane after it landed.