Fishermen in the eastern Chinese province of Jiangsu have been rewarded for finding “suspicious underwater devices” as part of a push by authorities to encourage people to be on the alert for spying equipment in local waters.

Nine devices were reported to the Ministry of State Security in 2018, six of which were “foreign devices capable of underwater investigation, identification and spying”, according to state news agency Xinhua.

Details of the devices and the amount awarded to the 11 fishermen, and seven other related individuals, were not revealed.

Jiangsu’s fishing community tends to concentrate its efforts around the East China Sea where Japanese and American naval patrols are common.

In an indication of how much the fishermen may have received, a fisherman in Lianyungang, northeastern China, was awarded 50,000 yuan (US$7,300) for discovering underwater devices in January 2018.

The 11 Jiangsu fishermen, and seven other related individuals, were presented with their rewards at an annual ceremony organised by the provincial authorities.

This is not the first time China has mobilised civilians against foreign spying in its waters.

In 2009, two Chinese fishing trawlers were among five Chinese ships which “harassed” an American naval surveillance vessel, the USNS Impeccable, in the South China Sea, south of Hainan.

In November 2018, according to Chinese media, national security authorities awarded prize money to a fisherman from Wenzhou, in the eastern coastal province of Zhejiang, who discovered a foreign underwater drone on a beach near his village.

Wenzhou Daily reported that the drone was identified as an unstaffed vehicle made by a Canadian developer.

Chinese fisherman were not the only ones picking up underwater devices in 2018.

Earlier this month, a Vietnamese fisherman picked up a training torpedo with Chinese characters off the coast of Phu Yen province in south-central Vietnam, according to local media reports.

In response, China’s defence ministry said the Chinese navy had lost a torpedo near the Hainan islands while conducting drills in early December which could have drifted closer to Vietnam.

“It was for training purposes and not aimed at any target,” the ministry said.

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