The Philippines announced Friday that it does not intend to invoke its mutual defense treaty with the US following an incident captured on video where the Chinese coast guard allegedly boarded two Philippine navy boats, with a Philippine sailor sustaining serious injuries. The Chinese Coast Guard sailors were attempting to block a resupply mission at the disputed Second Thomas Shoal in the South China Sea.

Philippines Executive Secretary Lucas Bersamin, who also heads the country’s National Maritime Council, suggested that the clash was “probably a misunderstanding or an accident.” During a briefing, he stated, “We are not yet ready to classify this as an armed attack. I think this is a matter that can easily be resolved by us and if China wants to work with us, we can work with China.”

China’s foreign ministry contested the Philippines’ account, with a spokesperson from the China Coast Guard claiming that their measures were legitimate and justifiable. The spokesperson stated:

The China Coast Guard strictly warned the Philippine vessels in accordance with the law, tracked and monitored the vessels all the way and effectively regulated them. China has indisputable sovereignty over the Nansha Islands, including the Ren’ai Reef, and its adjacent waters, and firmly opposes the illegal transportation of construction materials by the Philippines to the illegal grounded warship. The China Coast Guard will continue to carry out law enforcement activities in the sea areas under China’s jurisdiction according to law.

US State Department Spokesperson Matthew Miller underscored the terms of Article 4 of the 1951 Mutual Defense Treaty between the Philippines and the US, which binds each nation to support each other in the event of war, in a June 17 statement reinforcing US support for the Philippines in the South China Sea. Miller added, “PRC vessels’ dangerous and deliberate use of water cannons, ramming, blocking maneuvers, and towing damaged Philippine vessels, endangered the lives of Philippine service members, is reckless, and threatens regional peace and stability.”

China claims almost the entirety of the South China Sea, dismissing competing claims from the Philippines, Brunei, Malaysia, Taiwan and Vietnam, as well as an international ruling that its stance has no legal basis. These territorial disputes are considered potential flashpoints, potentially drawing the US into conflict with China if high seas confrontations result in armed conflict.

Tensions in the South China Sea have escalated in recent months, with the Philippine military pledging in June to defend fishermen’s rights against China’s “anti-trespassing policy” and recent authorization to detain foreign ships for up to 60 days without trial.