A Malaysia Airlines plane crashed in the disputed South China Sea on Friday, killing at least 11 people, including the pilot, and injuring 11 others, including two passengers.

Malaysia Airlines said in a statement that it had received a report of a crash at 10:20 a.m. local time.

A helicopter and firefighting aircraft were on the scene and a search and rescue operation was under way, the airline said.

Malaysia’s National Search and Rescue Agency said in the statement that the plane was “in distress after taking off from Kuala Lumpur International Airport.”

The crash occurred in the waters between Malaysia and Vietnam, a Thai-Malaysian border post.

The statement did not provide details about the passengers or the aircraft.

Malaysia is a key U.S. ally in Southeast Asia, where Beijing is embroiled in territorial disputes with Brunei, the Philippines and Vietnam.

China’s government has denied responsibility for the crash.

Malaysian Prime Minister Najib Razak was briefed on the crash by his national security adviser, Rear Adm.

Md.

Abdul Aziz Ali, according to the Malaysian government’s statement.

The airline was traveling from Kuala Kota Baru to the Beijing-bound Boeing 777 when it crashed, Malaysia’s statement said.

“It was a Boeing 777-200ER, Boeing 777, Boeing 737, Boeing 747, Boeing 787-8,” the statement said, referring to Boeing’s long-range 737-800 planes.

“The plane was carrying 239 people on board.

It was operated by Malaysian Airlines.”

Malaysia Airlines did not immediately respond to a request for comment from AP.

The Malaysia Airlines jetliner that crashed in a southern Chinese island chain was heading to Beijing from Kuala KL International Airport, Malaysia Airlines CEO Ahmad Jauhari Yahya said in an emailed statement to The Associated Press.

Malaysian authorities said a man and a woman were among the dead and that two other people were injured.

The plane’s pilot, who was a Chinese national, was pronounced dead at the scene, Malaysian Airlines said.

The two people on the plane with him had minor injuries, Malaysian officials said.

Malaysian officials earlier said they believed the plane went down on land.

China says it has sovereignty over the Spratly Islands, a group of small, uninhabited rocks that stretch from the coast of Malaysia in the far south to the western coast of Vietnam in the southwest.

China, a close U.N. ally, has also claimed most of the South China Seas as its own.

Malaysia has an air force and navy, and is one of the few countries with a military base in the country.

Malaysia and China have also maintained diplomatic relations, but tensions have been rising in recent years, especially over a territorial dispute in the South and East China Seas.

China has stepped up patrols in the area in recent months.

The crash comes as tensions between Beijing and Kuala Lumpur escalated further.

Malaysia, which hosts the largest U.E. military base outside China, has been the focus of the U.K.’s most vocal criticism of Beijing over a series of territorial disputes.

Malaysia says it needs to protect its sovereignty in the region and has expressed concerns about Chinese expansion.

It has also accused Beijing of sending troops into disputed waters in the Sprats.

China is Malaysia’s second largest trading partner, with more than $1.7 trillion in exports in 2016.

Malaysia said the jetliner was a 777-300ER with two engines and had a capacity of 972 passengers.