The Philippines has accused China of installing a “floating barrier” to stop fishing boats from entering a disputed area in the South China Sea.
The Philippines’ coast guard said the 300m (1,000ft) obstacle was preventing fishermen from working in a lagoon in the Scarborough Shoal.
China claims more than 90% of the South China Sea and seized the shoal in 2012.
Commodore Jay Tarriela of the Philippine coast guard said the barrier was discovered by a patrol on Friday.
Three Chinese coast guard boats and a Chinese maritime militia service boat installed the barrier when the Philippine vessel arrived, he said.