China says it has found a US submarine detection device

China said it had recovered a submarine-searching sonar that the United States allegedly dropped in a disputed part of the South China Sea.

An undated video shared Wednesday by Yuyuan Tantian — a social media account affiliated with state-run China Central Television — shows what appears to be a U.S. Navy P-8A Poseidon reconnaissance plane dropping multiple cylindrical objects.

One of them, the report said, fell into waters near Second Thomas Shoal in the Spratly Islands, known in Beijing as Ren’ai Reef. The reef is currently the hottest point in the Philippines’ territorial dispute with China and the site of a violent clash between their forces last week.

“After the incident, the China Coast Guard immediately went to the area to rescue and inspect unknown electronic devices in accordance with laws and regulations,” Yuyuan Tantian said.

The 40-second video then cuts to battery labels on the electronic device, which lists Ultra Electronics as the manufacturer. Ultra Electronics is a UK defense contractor that develops a range of marine products, from radar and electronic warfare products, from sonar buoys to electromagnetic interference filters.

Newsweek wrote to the Chinese Foreign Ministry and the U.S. Naval Pacific Command for comment.

Yuyuan Tantian quoted Chinese naval expert Yang Xiao as saying that U.S. forces could use devices like the recovered ones to detect Chinese submarines, as well as emit signals to jam Chinese operations.

The video points out that sonar can interfere with the echolocation abilities of dolphins and whales.

“The location where the US military aircraft dropped the detector was the waters near the Ren’ai Reef in the South China Sea,” the video reads. “Not only is the environment beautiful, but pods of dolphins play there.

“The noise generated by its sonar can disrupt the echolocation systems of dolphins and other sea creatures, causing disorientation and sometimes even driving them right to shore.”

The Strategic Situation Survey Initiative, a think tank founded by China’s Peking University, reported earlier this year that the United States sent P-8s and other types of “large reconnaissance aircraft” on about 1,000 sorties over the South China Sea last year.

China claims sovereignty over the vast majority of the resource-rich waterway, through which at least a fifth of global trade passes each year, according to estimates.

China’s vast claims overlap with the exclusive economic zones of several neighboring countries, including U.S. ally the Philippines.