All 347 passengers and 18 crew aboard flight 113, a Boeing Co 777 widebody, are safe, an airline spokeswoman said.

Pilots of flight 113 declared an emergency and reported a possible engine failure on the 777, Los Angeles International Airport said.

A witness on the ground described “bursts of flames” coming out of an engine.

The US Federal Aviation Administration said the plane returned and landed without incident.

Television station ABC-7 in Los Angeles aired video of the plane after takeoff that showed flames and smoke coming out of the right engine.

The plane landed around 12pm local time and was met by the Los Angeles Fire Department, the airport said. There has been no impact on other flights.

While the cause of the apparent engine failure was not immediately clear, it comes as Boeing faces intense scrutiny over twin deadly crashes involving its 737 MAX single-aisle jetliner.

The 737 MAX has been grounded worldwide since March.

Boeing and General Electric, which makes the GE90 engine for the 777 twin-aisle jetliner, did not immediately respond to requests for comment.

“You saw bursts of flames, little flames shooting out from the engine,” said Andrew Ames, a 36-year-old fitness professional in Los Angeles, who watched as the 777 ascended over the ocean after takeoff.

“It almost looked like backfire flames from a motorcycle or car.”

“I had never seen a plane spew flames repeatedly. Then it stopped. As soon as it stopped, I saw the plane bank left, like it was heading back to airport,” Ames said.

The Philippine Airlines spokeswoman said the flight crew noticed smoke in the plane’s second engine and declared an emergency landing and returned safely to the airport.

“All passengers are safe and sound,” spokeswoman Cielo Villaluna said.

“They are all being assisted to another flight.”