The last United Airlines 747 is greeted by water cannons after it makes its final landing at Dulles International Airport October 19, 2017 in Dulles, VA.

A mysterious odor in the cabin of a United flight leaving Baltimore-Washington Airport prompted pilots to divert the plane and make an emergency landing at Dulles International airport on Friday.

Seven passengers were sent to local hospitals for evaluation, according to the Metropolitan Washington Airports Authority, which represents Dulles International.

The aircraft, a Boeing 737, was headed to San Francisco International Airport and landed without incident, airport officials said. Fire and rescue personnel at Dulles responded to reports of an odor aboard United flight 1675.

United said it will rebook customers on other flights to San Francisco.

CORRECTION: This article was updated to correct which airports the MWAA represents. It's Dulles and Ronald Reagan Washington National.