The British Police has arrested a fourth person in connection with the killing of Indian student Anuj Bidve, who died following an "unprovoked" attack on Monday.
The unnamed man is the fourth arrest after another man and two teenagers were arrested in the last 24 hours. No further details were released about the three arrests.
Bidve, from Pune, was with nine Indian students on Monday when they were approached by two men in Salford. He was shot at close range after a "very short" conversation.
Bidve, 23, was a student of Microelectronics at Lancaster University.
Professor Bob McKinlay, deputy vice chancellor of Lancaster University, said Bidve had been "at the very beginning of a promising career and had only been at Lancaster for a short time. We are deeply saddened by his loss and our thoughts are with his family and friends, and we will do all we can to support them at this sad time."
In a statement, Bidve's family has said his death had left "a void in our lives."
"Anuj was a loving son, a super caring brother and first and forever a friend for many.
"He valued his relationships and put them over anything else," the family said in a statement released through the Greater Manchester police.
The police have not ruled out racism as a motive for the killing. The two men who approached the group of students at Salford were described as white men.
Without ruling out racism as motive, Chief Superintendent Kevin Mulligan had on Tuesday said: "This appears to be an unprovoked attack and we can't establish a motive at this time. We are investigating every possible aspect and we are in the early stages of the investigation, but we are not ruling anything out".
A post-mortem revealed that Bidve died as a result of "gun trauma" to the head.