The murder of an Indian student who was gunned down at point-blank range on Boxing Day is being treated as a "hate crime", police said today.
Anuj Bidve, 23, was shot in the side of the head as he walked with friends near their hotel in Salford, Greater Manchester, in the early hours of the morning.
Five people have now been arrested over the incident.
A 20-year-old man was arrested in the early hours of today, Greater Manchester Police (GMP) said.
A 16-year-old boy, two boys aged 17, and a 19-year-old man are also being held on suspicion of murder.
Speaking at a press conference today, Chief Superintendent Kevin Mulligan said detectives were not ruling out that the shooting might have been racially motivated.
He said: "A racially-motivated crime is when there is actual evidence to show that it is the actual motivation for the crime."
He said a hate crime, "by definition, is something that a community or anyone perceives is racially motivated".
Mr Bidve was in a group of nine male and female Indian students visiting Manchester for a short break over the Christmas holidays.
Police said the students, who had not been drinking, were walking from their hotel towards the city centre and became aware of two men on the other side of the street.
Mr Mulligan said no clear motive for the murder had been found and the investigation was "complex".
Police described the gunman earlier as a white male in his 20s who was wearing a grey top.
He is believed to have walked across the road and engaged Mr Bidve in a short conversation before producing the gun and shooting the student at close range to the side of the head.
The killer then ran back across the street before the pair fled on foot towards Asgard Drive and the Ordsall housing estate.
Mr Bidve collapsed to the ground and died in hospital a short time later.
Armed response units were sent to the scene at around 1.35am, police said.
Mr Bidve was studying for a micro-electronics postgraduate qualification at Lancaster University, and was described by tutors as "an outstanding applicant at the very beginning of a promising career".
His family in Pune, Maharashtra, said they had "lost faith in everything" as they struggle to come to terms with the tragedy.
Mr Mulligan said police were working with the Indian High Commission to help his family fly to the UK as soon as possible.