The fatal shooting of an Indian student has brought "shame" on the city where he was gunned down, a council chief said on Wednesday.
Anuj Bidve, 23, was shot at point-blank range as he walked with friends near their hotel in Salford, Greater Manchester, in the early hours of Boxing Day.
Police investigating the shooting have arrested a 16-year-old boy, two boys aged 17 and a 19-year-old man on suspicion of murder.
Norman Owen, leader of Salford's Liberal Democrats, said: "I am really concerned. If you look at the history over the last three or four years we have had some severe shootings in this city.
"We are being dragged down by this issue and the police have got to get into gun crime," said Mr Owen.
Asked if he thought this shooting had brought shame on the city, he responded: "It does. This city is trying to drive itself forward in many ways."
But he said Salford needed to "rid itself" of the gun "culture" and work with police, parents and schools to address it.
Police said a 16-year-old boy and 17-year-old boy were arrested yesterday on suspicion of murder.
A third teenager, also 17, handed himself into a police station at about 10.30pm last night and was arrested on suspicion of murder.
In the early hours of this morning a fourth man, 19, was also arrested on suspicion of murder.
All four males are being questioned and remain in police custody.
Chief Superintendent Kevin Mulligan, divisional commander for Salford, said today: "This is a fast moving investigation and we now have four people in custody.
"Those people will be questioned throughout the day by detectives and it is important we do not speculate on the possible motives for this murder.
"However, I would still appeal to anyone who has information about the murder to come forward.
"While we have made arrests, this is just the beginning of our investigation and we need people to come forward with anything they know."
He added: "I want to take this opportunity to praise the response of the Ordsall community who are clearly outraged by the murder of this young man and have come forward with information that is greatly assisting the investigation.
"We absolutely need this support to continue."
A large police presence, including armed officers, are patrolling in the Ordsall area and that will continue over the next few days, police said.