China has replaced a top official in Hong Kong as anti-government protests in the semi-autonomous territory enter their eighth month.

Luo Huining, the former Communist party chief for Shanxi province, has been appointed head of China’s liaison office in Hong Kong, the official Xinhua news agency said.

He replaces Wang Zhimin, who had assumed office in September 2017. Xinhua did not give a reason for the change.

The protests, which began in early June, have turned violent at times, with hardline demonstrators clashing with police. The violence has eased in the past month, but sporadic clashes have continued.

A huge and largely peaceful march on New Year’s Day degenerated into violence as some protesters attacked cash machines with spray paint and hammers, torn up from pavements.

Police used pepper spray, teargas and a water cannon to drive off the demonstrators, although a government statement said officers had deployed the minimum force necessary.

The protesters are demanding fully democratic elections for Hong Kong’s leader and legislature and an investigation into police use of force to suppress their demonstrations.