Two teenagers have been arrested on suspicion of murder after Indian student Anuj Bidve was shot dead in Salford, Greater Manchester.
Anuj, a 23-year-old micro-electronics student at Lancaster University, was gunned down at point-blank range as he walked with friends near their hotel in the city, in the early hours of Monday.
A 16-year-old boy was arrested on Tuesday afternoon, after a 17-year-old was detained followed the execution of an arrest warrant. Both are being held in custody.
"The 17-year-old boy was arrested on suspicion of murder after a warrant was executed in the Salford area the early hours of today," a spokesperson for Greater Manchester Police said.
"He remains in custody for questioning."
Anuj was part of a group of nine male and female Indian students who were 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.
The gunman, a white male in his 20s who was wearing a grey top, walked across the road and engaged the victim 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.
Armed response units were sent to the scene at around 1.35am.
Anuj, from Pune, Maharashtra, collapsed to the ground and died at hospital a short time later.
Greater Manchester Police (GMP) said it was an "awful" attack and pledged to "leave no stone unturned" in the hunt for the killer.
Chief Superintendent Kevin Mulligan, divisional commander for Salford, said a racial motive for the killing was not being ruled out, adding: "We are investigating every possible aspect."
Speaking from Pune, Anuj's brother-in-law Rakesh Sonawane, 30, who is married to the student's sister Nehal, said the devastated family had "lost faith in everything".
Anuj had arrived in the UK in September after completing an electronics degree at Pune University.
"Anuj had been very happy. It was his dream to go to the UK but unfortunately his dream could not last longer than three months," Mr Sonawane said.
He added that Anuj had planned to return to India "to serve his nation" following the postgraduate studies in Lancaster.
The student was described as "clever and sporty", and a fan of football, supporting Manchester United.
Mr Sonawane added: "He loved to travel and make friends. He had lots of friends. You only have to look at his Facebook page to see how many friends and followers he had.
"We have completely lost faith in everything."
He added that the family have received lots of messages of support, especially from the Indian student community in Lancaster.
They have spoken to some of those who were with Anuj when he was killed and said the eight students have now returned to the university.
"They are equally disturbed and shocked," the brother-in-law said.
Tributes have been left on Facebook, including one page set up by a fellow Lancaster student which plans a "peace march" in the young man's memory.
According the page, set up by Sonakshi Saran, Anuj "was killed for not answering a simple question - What's the time?"
GMP have not disclosed what was said during the short conversation between the killer and his victim.
The student's father, Subhash, a branch manager with an energy company, has called on the UK government to speed up the process of returning Anuj's body to the UK.
In a message on his son's Facebook wall, he said: "Please help in getting Anuj Bidve's dead body back to India. He was shot in Manchester today morning. We appeal to all his friends in UK and India to help spread the word. Please help us get Anuj back. Please share this message."
Mr Sonawane said he had tried to contact the Indian High Commission in London but it has been shut for Christmas.
He added: "We are asking the UK government and the Indian Embassy to expedite the return of Anuj's body to his family at the earliest opportunity."