Amid ongoing protests in Hong Kong, police were hunting for six suspects after petrol bombs were hurled at the city’s metro station on Thursday that forced the rail operator to immediately evacuate the area and close the site.

The incident took place just hours after police arrested a 29-year-old man and two teenagers in separate incidents, the South China Morning Post newspaper reported.

The Mass Transit Railway (MTR) Corporation said black-clad “rioters” hurled petrol bombs at two escalators and a shop at the Ngau Tau Kok station in Kowloon at around 1 a.m.

They also vandalised ticket machines and other facilities on the concourse.

The suspects fled before police arrived, no one was injured, and rail services resumed later in the day.

Earlier in the month, Hong Kong’s protests are largely leaderless and organised online. They were initially sparked by a now-abandoned attempt to allow extraditions to the mainland but have since morphed into a popular revolt against Beijing’s rule.

Radicals had caused extensive damage to 85 of 94 MTR stations, so far.

Affected facilities include ticketing machines, surveillance cameras, lifts and escalators and rolling shutters.

In November, China had accused UK human rights chief, Michelle Bachelet of “inappropriate” interference in the country’s affairs, after she called for investigations into alleged excessive use of force by police in Hong Kong.

Hong Kong’s protests started nearly six months ago in June against proposals to allow extradition to mainland China, a move many feared would undermine the city’s judicial independence and endanger dissidents.

In 2018, the Hong Kong government had disqualified the candidacy of another pro-democracy activist, Agnes Chow, for the Legislative Council by-election in March of the same year due to her stance on advocating self-determination for the former British colony.

The controversial China extradition bill was withdrawn in early September but the movement has morphed into a wider campaign for greater democracy and against alleged police brutality.