WATCH: Tensions escalate in South China Sea as China clashes with Philippines

Chinese Coast Guard hold knives and machetes as they approach Philippine troops on a resupply mission in the Second Thomas Shoal ©AP/AP

The Chinese damaged the boats and attacked the Filipino personnel, who resisted without weapons. China accused the Philippines of trespassing, while the US reiterated its defense obligations to its ally. Tensions have escalated since last year around the shoal, where a grounded Philippine warship serves as a territorial outpost.

© Euronews