A Chinese Navy helicopter flies within three meters of a surveillance flight over Bajo de Masinloc in the West Philippine Sea. Philippine Coast Guard

The US State Department on Thursday backed the Philippines and condemned the reckless actions of a Chinese helicopter that flew near a Bureau of Fisheries and Resources plane in the vicinity of Scarborough Reef.

In a statement, US State Department spokesperson Tammy Bruce condemned the “ unsafe and irresponsible actions by the Chinese People’s Liberation Army-Navy (PLAN) to interfere with a Philippine maritime air operation in the vicinity of Scarborough Reef.”  

“A Chinese helicopter came within three meters of a Philippine Bureau of Fisheries and Resources plane conducting routine overflight, endangering the safety of the aircraft and its crew.  This incident follows China’s separate unsafe and unprofessional maneuver on February 11 that endangered an Australian aircraft that was conducting a routine maritime patrol in the South China Sea,” she said.

Bruce said reckless Chinese actions such as these are a “threat to navigation and overflight in the South China Sea.”

“We will continue to support our allies and partners to ensure a free and open Indo-Pacific. We call on China to refrain from coercive actions and settle its disputes peacefully in accordance with international law,” she said.

She noted that the 1951 United States-Philippines Mutual Defense Treaty extends to armed attacks on Philippine armed forces, public vessels, or aircraft – including those of its Coast Guard – anywhere in the South China Sea.

PCG spokesperson for the West Philippine Sea Commodore Jay Tarriela earlier said the PLA Navy helicopter, identified by plane tail number 68, flew dangerously close to the BFAR plane.

"This reckless action posed a serious risk to the safety of the pilots and passengers during the MDA flight," Tarriela said in a statement.

The PLA Navy helicopter came as close as three meters to the portside (left) of and above the BFAR aircraft.

Tarriela said the incident raises significant concerns regarding the PLA Navy's violation and "blatant disregard for the International Civil Aviation Organization's international aviation regulations."

"The PCG and BFAR remain committed to asserting our sovereignty, sovereign rights and maritime jurisdiction in the West Philippine Sea, despite the aggressive and escalatory actions of China," he added.

Bajo de Masinloc is located 124 nautical miles off Masinloc, Zambales, and is within the Philippines' 200-nautical-mile exclusive economic zone. The shoal, however, has been under China's control since 2012.

China claims the South China Sea almost in its entirety despite an international ruling in 2016 concluding this has no legal basis.

Tarriela told reporters Tuesday's incident was the first time a PLAN helicopter had been used against a Philippine patrol plane in such a manner.

"Less than 10 feet. So that's very dangerous. It can definitely affect the stability of the aircraft," Tarriela told a briefing after the incident.

Asked if the encounter marked an escalation, Tarriela said he believed China was taking a "calibrated approach" to such interactions, while reiterating President Ferdinand Marcos's declaration that the country's mutual defense treaty with the United States could be invoked if a death were to result.

Tian Junli, spokesperson for China's Southern Theater Command and senior colonel of the Air Force, said the Philippine aircraft had "illegally intruded into Chinese airspace over Huangyan Island", using the Chinese name for the shoal.

He said naval and air units were deployed "to track, monitor, warn, and expel the aircraft in accordance with the law and regulations", adding that the "actions of the Philippine side seriously violated China's sovereignty".

The Philippine government plans to issue a formal diplomatic protest over the incident, according to the National Maritime Council. With Agence France Presse

Philippines to protest 'dangerous' China helicopter maneuvers: official