The fishermen who went out to sea didn't know about these things in the past, so they weren't so vigilant. It was all because the sea staff often visited the fishermen, slowly making them vigilant. Hence, every time they went into the sea and caught strange things, they would quickly turn them in and not secretly transport them home.
If it were in the past, they would have moved the strange items back to the village and their homes. Sometimes, they wouldn't take it to heart. They would find them a hindrance and throw them back into the sea.
The maritime police immediately recognized that the strange thing handed in by the fishermen was an 'underwater detector'. That day, the maritime police and the navy of the entire south moved out to search for how many 'underwater detectors' there were in China's waters.
These things were not to steal the resources of the country's territorial sea. They were prepared in advance for future combat.
