A Vietnamese official on Wednesday accused China of attacking its fishermen in three separate incidents over the past week in the disputed South China Sea.

Nguyen Thanh Hung, head of the fisheries union in Binh Chau village in central Quang Ngai province where the fishermen came from, said a Vietnamese trawler with 12 crew was intercepted by a Chinese military vessel while fishing near the Paracel islands on Sunday. He said the Chinese seized their catch and fishing equipment.

Hung said this followed incidents last week where Chinese military vessels used water cannon to try to drive away a Vietnamese fishing boat, injuring two fishermen, while another Vietnamese fishing boat was intercepted and robbed of its catch and equipment while fishing near the Paracels.

"I strongly protest these Chinese actions," Hung said by telephone from Quang Ngai province. "This is our traditional fishing grounds, it's within Vietnamese sovereignty and our fishermen have been fishing there for generations."

The incidents come as Vietnam's foreign minister, Pham Binh Minh, who is also the deputy prime minister, began a three-day visit to China on Wednesday to talk about bilateral cooperation, with the situation in the South China Sea expected to be high on the agenda.

Vietnam claim sovereignty over the Paracels, which were occupied by China after it drove off the U.S.-backed South Vietnamese navy in 1974, one year before the end of the Vietnam War.

The two communist neighbors along with the Philippines, Malaysia, Brunei and Taiwan claim all or parts of the South China Sea.

China's massive land reclamation projects in the Spratly islands over the past two years have alarmed its neighbors and the United States.

Chinese Foreign Ministry said Tuesday that the reclamation projects on seven reefs and atolls will be completed within days and will follow up with building infrastructure for military and civilian purposes.

The U.S. has said it takes no side on the sovereignty questions, but insists on the right of free navigation and urges all parties to negotiate a settlement.