A Norwich nightclub fears it could be forced out of business after seeing its opening hours cut because of police complaints of serious violence and disorder.

Kartel in London Street has been the scene of repeated disturbances in the past two months, including an incident when a customer climbed on to the roof and dislodged a pane of glass which fell and injured five people, and a large-scale brawl in which doormen had to retreat inside the building as drunken customer tried to break in, according to police officers.

They applied to councillors to change its licensing after a disturbance outside the club last week saw doormen rolling on the floor brawling with drunken customers

Councillors yesterday agreed to make the interim changes ahead of a full review, including changing the last entry from 3.15am to 2.45am and closing an hour earlier at 3am – changes which co-owner Brad Baxter said would spell the end of the club if made permanent.

'If I have to go back to [last entry at] 2.45am then we are 100% going to go out of business,' he said, adding that up to 70% of his trade was done after 2.30am as staff from other bars arrived after their shifts.

Andy Owens, for Norfolk police, told Norwich City Council's licensing sub-committee the primary concern was 'the lack of ability to manage those within the club in a responsible manner'.

'We have concerns over the incident [on January 29] and how it was managed on the day and the track record of the premises,' he added.

He said the catalogue of incidents showed a 'clear pattern', with the majority taking place after 2am and involving people who were drunk.

Councillors were shown CCTV footage of a fight on January 29 in which several men ejected from the club attack the two doormen, who eventually retreated inside and locked the doors, trapping all remaining customers and staff inside.

Describing the scene to councillors, Inspector Darren Brooks of the licensing team said: 'In 17 years of licensing I've not seen a lack of control on the doors to that degree.'

Mr Baxter disputed the police's version of many of the incidents, arguing that they had arisen when people became angry at the club's legitimate attempts to eject them.

He apologised for the night of the brawl, saying the club busy because of a Norwich City match.

Mr Baxter said the club had tried to work with police and was implementing new CCTV systems, health and safety plans, and would be joining the radio network linking night-time venues. He added the club had a strong record of refusing entry.

Chair Ralph Gayton said: 'We have a responsibility to ensure these sorts of premises are run to the best advantage of everyone in the city.'

Councillors also ordered the club to update CCTV and radio systems within 10 days, ahead of a full review within 28 days.