The families of two men who were shot dead in Milton Keynes have paid tribute to them.
Somali Amin Ahmed Ismail, 18, died in hospital after the shooting in an alleyway in Fishermead on Thursday.
The other victim, Mohamed Abdi Farah, 19, of Birmingham, who was also originally from Somalia, died from a single gunshot wound to the head.
Two men, aged 21 and 33, and a boy, 13, have been bailed pending further inquiries.
Thames Valley Police said the victims were known to them over low-level criminal activity.
Detectives have ruled out the killings being gang-related.
Mr Ismail's family said in a statement that the teenager had come to England at 10 years old.
"He was the only boy in the family and grew up with his four sisters who he loved very much," the statement said.
"He also leaves behind a stepbrother and one stepsister."
'Very, very kind'
His family said Mr Ismail had been educated at Southall College and Henley College in Coventry where he was "particularly good" at maths and science.
"Amin was good at education and wanted to achieve a degree and a masters so that he could help look after his mum and sisters," the statement added.
"Amin had a good personality and was very, very kind. Being the only brother he always looked after his sisters and used to tell us he would look after the whole family.
"He will be missed very much."
Mr Farah's family said he had only been in England for four weeks.
"We, Mohamed's family, are deeply saddened and shocked at what can only be described as the tragic and senseless death of our son, brother, nephew and grandson.
"We cannot put into words the pain we are feeling, only to say that he did not deserve to die in this way. Mohamed will always be in our hearts and will never be forgotten."
They said Mr Farah was a "very likeable, sociable, and friendly individual, who was looking to continue his studies and go to university".
"But sadly that bright future that he was looking forward to has been cut short by a senseless killer," the statement added.
Earlier on Monday, police said officers were conducting house-to-house inquiries and viewing hours of CCTV in a search for the men's killers.