Unidentified assailants attacked and beat a prominent Vietnamese protester in the capital Hanoi on Sunday, sending him to the hospital amid a recent surge of similar assaults on dissidents by plainclothes attackers believed to be linked to the police. La Viet Dung, an anti-China activist and member of a local soccer club, called the attack a move to "terrorize" his team, called No-U in a reference to the U-shaped "nine-line dash" that marks Beijing's disputed claim to the South China Sea. "The attackers had to have come either from the security forces or the police," Dung said, speaking to RFA's Vietnamese Service on July 11. "They see No-U as a platform for anti-China protests, so they want to disrupt our activities," he said. "The police followed us all day yesterday," Dung said, adding, "They have been harassing the No-U team for quite some time, and this has been happening more frequently recently." The No-U soccer club, which plays each weekend in Hanoi, was founded five years ago to provide opportunities for anti-China activists and other dissidents to "meet, talk and strategize," Agence France-Press said in a report on Monday. China's territorial claims and artificial island construction in the South China Sea have sparked frequent anti-Chinese protests in Vietnam, which the one-party communist government in Hanoi fears as a potential threat to its own political control. Beaten, robbed Police and unidentified attackers meanwhile moved at the end of last week against a former political prisoner and another group of activists, forcing them separately into cars and beating them before letting them out in remote areas, sources said. Nguyen Viet Dung, an activist and former prisoner, was stopped by police in Saigon on July 9 and taken to north-central Vietnam's Nghe An province, where he was forced into another car by unknown assailants and brutally beaten before being pushed out into the street, Dung told RFA. "I was attacked even more severely about two months ago," Dung said. "This time, my mouth was swollen." Also on July 9, eight activists were stopped and robbed of their cell phones and money while on their way to a wedding in Cua Lo town in Nghe An, one victim named Nguyen Trung Truc told RFA on Monday. After stopping outside Cua Lo to buy gifts for the wedding, the group was surrounded by "about 40 to 50 people" traveling in cars and on motorbikes, Truc said. "They took our keys and separated us, forcing us into their cars," he said. "There were security people inside the cars who attacked us, and they drove for about 15 or 20 kilometers before dragging us out, still beating us," Truc said, adding, "I fainted twice." Forced out at the border between Nghe An and Ha Thin provinces, the activists were then stripped of their clothes and left, Truc said. "Some of us only had underwear on," he said. "Some had nothing on at all." A reporter's call seeking comment from authorities in Hanoi was turned away on Monday , with one official-Nguyen Duc Chung of the Hanoi People's Committee-saying he was in a meeting and unable to speak.