A VIETNAMESE captain has been killed and a cargo ship owner injured in a violent raid on a vessel in the hotly-disputed Tonkin Gulf. Reports reached Hanoi yesterday of the attack on the general cargo carrier, BS027, which saw three men armed with AK-47 rifles strafe the vessel. Captain Nguyen Ngoc Tan died instantly as the men opened fire in the night-time raid. The Lao Dong newspaper put the attack 30 kilometres southeast of Ha Mai Island, off the picturesque Ha Long Bay - in the same area as a string of alleged recent incursions by Chinese fishing boats. Last month Vietnam publicised 10 alleged incursions in a diplomatic exchange between Hanoi and Beijing over ongoing territorial disputes covering the Gulf and the Spratly and Paracel Island groups. Vietnam is said to have stepped up naval patrols across large areas to ward off increased fishing activity by Chinese boats and oil research operations. Certain fields are claimed by both Vietnam and China. The disputes are expected to feature prominently in closed-door talks during the visit to Vietnam this weekend of Chinese President Jiang Zemin.