Hong Kong police arrested a man on Tuesday after he allegedly attacked a U.S. consulate general employee, “leaving him bleeding in the street” outside the consulate.

Police arrested a 35-year-old man at his home in the Tuen Mun area of Hong Kong on Tuesday night after identifying him from security camera footage of the incident earlier that day. The man has been previously connected to other crimes, a police source told the South China Morning Post (SCMP).

A 43-year-old American working as a facilities manager at the U.S. consulate general “had left the consulate on Garden Road at about 3:35 pm on Tuesday and was walking downhill when the suspect approached him from behind,” the report stated.

“The assailant then punched him twice in the head before running off,” the police source told the SCMP.

The victim returned to the consulate after the attack, where a colleague called for help from city emergency services; he was later sent to a nearby hospital for treatment. According to the report, the consulate is located in an area of Hong Kong regularly patrolled by the city’s counter-terrorism officers.

A U.S. consulate general spokesman confirmed that a consulate employee was assaulted on Tuesday “by an unknown individual,” adding that the victim’s injuries were not life-threatening.

“We are working closely with the Hong Kong Police Force regarding this incident. We cannot speculate on the assailant’s motives at this time,” he said.

“Occasional incidents involving the [U.S.] consulate have taken place in the past. A man from the mainland [China] was jailed for four weeks after vandalizing the building by painting words on a gate in August of last year. He admitted at the time he was not happy with Americans,” the Hong Kong-based SCMP, owned by China’s Alibaba Group, noted.

Hong Kong has been caught in the middle of increasingly strained relations between the U.S. and China in recent weeks. On August 19, the U.S. State Department suspended three bilateral agreements with Hong Kong, including “the surrender of fugitive offenders, the transfer of sentenced persons, and reciprocal tax exemptions on income derived from the international operation of ships.”

On August 7, the U.S. sanctioned Hong Kong’s pro-China leader, Carrie Lam, along with ten other current and former Hong Kong and Chinese officials for aiding Beijing’s imposition of a new national security law on the city. The far-reaching law has undermined Hong Kong’s traditional semi-autonomy, prompting the recent U.S. diplomatic actions against the city.