NEWARK, N.J. — A United Airlines Boeing 787 flying from London to Houston was diverted to Newark, N.J., on Thursday because of a low engine oil indicator, the second unscheduled landing for Boeing's newest plane this week.

The Federal Aviation Administration said that United Flight 125 landed safely at 2:10 p.m. at Newark Liberty International Airport outside New York City. The agency said it would look into the incident.

United said there were 218 passengers, four pilots and 11 flight attendants on board. United spokeswoman Christen David said most of the passengers were put on a Boeing 767, which left Newark and was scheduled to arrive in Houston on Thursday evening.

Boeing spokeswoman Kate Bergman said the company would work with engine manufacturer General Electric Co. to conduct maintenance and testing work and return the plane to service.

Bergman said that the incident was unrelated to another unscheduled landing involving a United Boeing 787 earlier this week.

On Tuesday a United plane heading to Tokyo from Denver was diverted to Seattle because of what the airline described as an oil filter issue. The airline put up about 200 passengers overnight in a hotel, then flew them to Tokyo on Wednesday on another 787.

The 787, which Boeing calls the Dreamliner, is under unusual scrutiny because it was grounded worldwide for three months after lithium-ion batteries overheated on two of the jets.

Boeing redesigned the battery system to the FAA's satisfaction, and airlines around the world resumed using the planes last month. United is the only U.S. airline that operates the 787.

"The 787 is a great airplane, and we know it will continue to receive heightened attention when reliability events occur in service," said Bergman, the Boeing spokeswoman.

The Dreamliner is Boeing's most technologically advanced airliner, with lightweight materials and other innovations designed to boost fuel efficiency. The fuel efficiency makes it suited for long flights including international routes.

At this week's Paris Air Show, Boeing has been taking more orders for the original model and a planned larger version called the 787-10.

The 787 is assembled at Boeing plants in Everett, Wash., and North Charleston, S.C. The company's corporate offices are in Chicago.