Police and pro-democracy protesters have clashed in a battle for territory in Hong Kong.

Protesters rushed to reoccupy their camp in the Mong Kok district that had been cleared by police and reopened to traffic hours beforehand. Riot officers are reported to have used pepper spray and batons against the demonstrators who shielded themselves with umbrellas.

Thousands of protesters are said to have been involved in the demonstrations. 

It marked the fourth night that violence has broken out after a fortnight which has been relatively quiet. The first week of the protests saw major clashes with police.

Leaders on both sides have called for calm. They also said that talks between the protest's leaders and delegates from the Hong Kong government will take place on Tuesday.

The protests have been underway since late September.

The protesters say Chinese authorities have limited their choice of candidates for the 2017 election. They have accused Hong Kong's Chief Executive, CY Leung, of failing to challenge the Chinese Communist Party and their new rules for election candidates.