Media playback is unsupported on your device Media caption Chief Executive CY Leung: "We have to draw a line between possibilities and impossibilities"

Hong Kong's government is ready for new talks with student protesters next week, its chief executive has said.

CY Leung was speaking after scuffles between protesters and police continued for a second night on a major road near government buildings.

He said officials had been negotiating with students via mediators this week.

The protests were sparked by a Chinese government ruling that limits who can stand as a candidate in Hong Kong's leadership elections in 2017.

Rising tensions

The demonstrations are in their third week, with protesters occupying key parts of the city to try to pressure the authorities to implement greater political reforms, including fully free elections.

Thousands of people took to the streets at the beginning of the demonstrations but the numbers have dwindled in recent days.

"Over the last few days, including this morning through third parties, we expressed a wish to the students that we would like to start a dialogue to discuss universal suffrage as soon as we can and hopefully within the following week," Mr Leung told reporters.

Image copyright Getty Images Image caption Riot police have used pepper spray to clear protesters in recent days

He said that the authorities would continue to restore order in Hong Kong in accordance with its laws "as quickly as we can", including the normalisation of traffic.

China will not retract its decision to vet candidates eligible to stand in Hong Kong's 2017 elections, he added.

Chief Secretary Carrie Lam cancelled scheduled talks with student leaders last week, saying it was impossible to have constructive dialogue with them while they continued to occupy key areas of the city.

Investigation launched

Tensions between the two sides have escalated over the past two days, with serious clashes between police and protesters trying to re-occupy a main road near the chief executive's offices.

Many demonstrators said they had returned to the area - an underpass on Lung Wo Road - after watching a video showing plainclothes police officers beating an unarmed protester, sparking public outrage.

Image caption Ken Tsang's lawyer says the beatings continued even after he was in police custody

But touching on the subject, Mr Leung told reporters on Thursday "we should not politicise this incident".

The US has called for a swift, transparent and complete investigation into the incident.

Hong Kong's Secretary for Security Lai Tung-kwok earlier said there was "concern" over the video.

On Thursday police said that seven officers had been suspended pending an investigation into the alleged beatings.

Media playback is unsupported on your device Media caption Protester Pen Ng: "We have a chance to give out our opinion"

"If any individual officer is suspected of using excessive force, police will investigate it in a just and impartial manner," said senior superintendent Kong Man-keung, quoted by AFP news agency.

The video shows the protester, named as social worker and member of the opposition Civic Party Ken, dragged handcuffed by police and thrown to the ground, then being assaulted for several minutes.

He was later taken to hospital. Mr Tsang's lawyer, Dennis Kwok, told the BBC his client had serious injuries and that the beatings had continued while he was in custody.

Hong Kong democracy timeline

1997: UK gives Hong Kong back to China under a 1984 agreement giving it "a high degree of autonomy" for 50 years

2004: China says it must approve any changes to Hong Kong's election laws

June-July 2014: Pro-democracy activists hold an unofficial referendum on political reform; both sides hold large rallies

31 August 2014: China says it will allow direct elections in 2017 but will pre-approve candidates

22 September 2014: Student groups launch a week-long boycott of classes

28 September 2014: Occupy Central and student protests join forces and take over central Hong Kong

2017: Direct elections for chief executive due to take place

Q&A: Hong Kong's democracy controversy