HOUSTON — The pilots of a Boeing 787 that left Houston bound for Denver circled back to Houston after a mechanical problem.

It's the third time in the past week that a flight involving Boeing's newest plane was cut short for a mechanical reason.

A United Airlines spokeswoman said Monday that Flight 94 returned to Houston shortly after takeoff on Sunday because of "a brake indicator issue."

Spokeswoman Jennifer Dohm said the flight made an emergency landing as a precaution, and a maintenance team was examining the plane. She said the airline made other accommodations for the stranded passengers.

Last week a United 787 made an unscheduled landing in Seattle on a Denver-to-Tokyo flight because an indicator showed a problem with the oil filter, and a London-to-Houston flight stopped in Newark, N.J., because of an indication of low oil level.

Boeing officials said those two events were unrelated to the battery issues that led regulators to ground all 787s worldwide for about three months this year. The Federal Aviation Administrators approved 787s to fly again after Boeing made changes to the lithium-ion battery system.

Boeing calls the plane the Dreamliner. It is made largely of light, composite materials that help boost fuel mileage, making it attractive to airlines, which have ordered about 900 of them. About 50 are in airline fleets around the world. United is the only U.S. airline using the plane.