HONG KONG — Seven police officers were arrested in Hong Kong on Wednesday, accused in the beating of a pro-democracy protester last month.

The officers, who were not identified, were arrested on charges of “assault occasioning actual bodily harm,” a police statement said. In the predawn hours of Oct. 15, Ken Tsang, a social worker, was kicked and beaten by a number of police officers in an episode that was filmed by a television crew and heightened animosity between the Hong Kong police and protesters after it was shared on social media.