There are other pressures. For example, the officials said they estimate the People’s Liberation Army Navy has placed as many as 150,000 Chinese commercial fishing vessels under its direction, even though they are not official Chinese navy. The Chinese fishing vessels make coordinated attacks on Vietnamese fishermen, the officials said, ramming and sometimes sinking boats near the Paracel Islands. China took the territory from Vietnam in the 1970s and has militarized some of the islands. The area remains a traditional fishing area for the Vietnamese.