The Philippines' foreign ministry recently summoned Beijing's envoy to  complain about the China Coast Guard firing water cannon at a Philippine Coast Guard ship while it was escorting a civilian convoy on the South China Sea.

In response, the Chinese government reiterated its demand that the Philippines remove the BRP Sierra Madre, a rusty World War II-era naval ship that Manila deliberately ran aground in the Ayungin Shoal (Second Thomas Shoal) in 1999 to serve as a military outpost in those contested waters, Radio Free Asia reported.

The convoy of Philippines ships was on a mission to deliver food, water, fuel and other supplies to troops stationed aboard the BRP Sierra Madre.

According to reports, the incident happened during this time.

While meeting with the Chinese envoy on Monday morning, Manila conveyed “the strong protest of the Philippine government to the blocking and water cannon operation by the Chinese Coast Guard and Chinese maritime militia vessels against Philippine indigenous boats,” Philippine Department of Foreign Affairs spokeswoman Ma. Teresa Daza told reporters as quoted by RFA.

The Philippine convoy was “conducting [a] regular rotation and resupply” mission to Ayungin Shoal, she said.

The Philippine government also expressed disappointment that it could not reach China’s foreign ministry through a hotline established between the countries earlier this year to improve communication during incidents related to the South China Sea, she said.