MANILA, Philippines (AP) — The U.S. deployed two warships Wednesday in a disputed South China Sea shoal where two Chinese ships collided earlier in the week while trying to drive away a smaller Philippine ship in a high-seas accident that raised alarms about maritime safety.

China’s military announced that it had monitored and “drove away” a US Navy destroyer that sailed close to the Scarborough Shoal in the South China Sea. This shoal is a small group of rocks and reefs but has become one of the most hotly contested areas in the region.

The Philippines expressed serious concern on Tuesday over what it called "dangerous manoeuvres and unlawful interference" by Chinese vessels during a coast guard supply mission for Filipino fishermen in the Scarborough Shoal in the South China Sea.