(CNN) -- A malfunctioning jet engine on an Air Canada flight caused burning hot debris to fall to the ground after takeoff, an official with Canada's Transportation Safety Board said Tuesday.
The incident Monday, which involved Air Canada Flight 001 bound for Tokyo from Toronto with 318 passengers and 16 crew members aboard, damaged vehicles on the ground and forced the Boeing 777 to return to Toronto. No injuries were reported.
Don Enns, a regional manager at the independent Transportation Safety Board of Canada, told CTV and CP24 on Tuesday that "some sort of failure" inside one of the plane's two engines disrupted the airflow, causing part of the turbine section to fly out the back.
"Those pieces as they were liberated from the engine, they came out the back of the engine," Enns said. "Essentially, it just fell out the back of the engine, fell down, and unfortunately, we had cars underneath them."
He called such an occurrence "very rare," saying the last time he could remember a similar incident was a decade or more ago. Engineers would dismantle the engine involved and study similar engines to try to learn why the malfunction occurred, Enns said.
Boeing said in a statement that it "stands ready to assist the Canadian regulator, if we are asked to participate. Per international rules Boeing has to be asked by the regular to participate in the investigation."
Boeing said it would provide technical expertise about the airport and "The engine manufacturer, GE, will have a similar role."
For its part, GE said in a statement that it had sent a technical representative to Toronto for the investigation. "The GE90 engine model powering this aircraft is among the world's most reliable engines ... The GE90 engine fleet, with more than 1,400 engines in airline service, has accumulated close to 30 million flight hours and no aviation accident has ever been attributed to the engine," the GE statement said.
The flight took off 2:10 p.m. ET Monday, but one engine then shut down, prompting the flight crew to follow "standard procedure" and return to Toronto Pearson International Airport, said Air Canada spokesman Peter Fitzpatrick.
The crew requested an emergency landing, which Fitzpatrick said was standard because it gives certain planes first priority, though he also noted the aircraft involved is designed to run on a single engine if necessary.
The plane landed normally, and passengers returned to the gate, according to Fitzpatrick. Constable George Tudos, spokesman for police in the regional municipality of Peel, said the aircraft returned to Toronto's airport at 3:53 p.m.
More than an hour before that, around 2:30 p.m., people began reporting seeing smoke, and one spotted what may have been debris coming from a large airliner, according to Tudos. At least three vehicles on the ground were being investigated for damage.
Sarabjit Sandhu told CP24, a CNN affiliate, that she and her husband had just gotten gas at a Petro-Canada station in Mississauga, outside Toronto, when they "heard a big noise, a bump, like boom."
A number of vehicles in the service station's parking lot were damaged, including a Nissan Altima with its back window shattered to pieces while its owner was inside the station's convenience store. Pieces of gray, heavy material littered the scene, according to CP24.
"It was so hot you couldn't even touch it," Sandhu said of the debris.