Tributes have been paid to a father and son shot dead within an hour of each other in a double killing that has rocked two villages in Cambridgeshire.
Detectives say they are investigating whether a custody battle was linked to the deaths just six miles apart.
The victims have been identified by friends and neighbours as builder Gary Dunmore, 57, and his 32-year-old son Josh Dunmore, who had his own building company.
Police are not confirming their identities until formal identification has been carried out. Three people have been arrested on suspicion of conspiracy to murder following the shootings on Wednesday evening.
A neighbour described Gary Dunmore as a “legend” who was “friendly, happy, smiley” and “did not have a malicious bone in his body”.
Josh Dunmore, who was a father to a young son, was a “passionate guy”, he said.
A friend described Josh as “an amazing person and dad”, whom she was going to miss. She wrote on social media: “I cannot believe it…. I love you always josh and will always remember our laughs and jokes and cherish our memories and friendship forever. Sleep well josh.”
Another friend, who described Josh as his “best friend for years”, wrote on Facebook of how he was “still in shock [and] always will be”, adding he was going to miss him.
A floral tribute laid at the scene said Josh’s son was “a very lucky boy to have a dad like you”, while another said he “fought every day” for his “precious boy”.
Cambridgeshire Police were called to reports of gunshots at a property in Meridian Close, Bluntisham, just after 9pm on Wednesday.
They said the body of a 32-year-old man was found there with a bullet wound.
At 9.37pm, officers were called by a person in Sutton, near Ely, also reporting hearing gunshots. The body of a 57-year-old man was found with shot wounds at a property in The Row.
Detective Chief Superintendent Jon Hutchinson, of Cambridgeshire Police, said: “Working with local residents and family members we quite quickly established that the two victims were related and they were father and son.”
He said the primary line of investigation was that the killings were over a “familial issue”.
“It’s been widely reported in the media that this may relate to a custody battle,” he said. “I can confirm that is an active line of inquiry for us.”
A 27-year-old man and a 33-year-old woman, who police say are from the local area, were arrested at a hotel just outside Cambridge on Wednesday night.
Armed officers arrested a 66-year-old man on the motorway in the Worcester area in the early hours of Thursday.
“Following his arrest, his vehicle was searched and I can confirm we have recovered a firearm,” Mr Hutchinson said.
Police are investigating whether the firearm was legally owned.
A tribute left to Josh in Bluntisham said: “This week was supposed to be a celebration for you and your precious boy.
“I pray that you can rest in peace knowing you fought every day for (him).”
Another said: “Josh, you shined such a bright light over everyone around you.
“It was impossible not to smile when you’re around. You’re going to be missed so much.”
A further tribute said “rest easy Josh”, adding: “Your son was a very lucky boy to have a dad like you.
“Your bubbly personality will be dearly missed.”
A neighbour of Gary Dunmore, who gave his name only as Stuart, said: “He was so friendly, happy, smiley - just the perfect neighbour.”
The 42-year-old software worker added: “If he heard you pant in the garden... he would pop his head over the fence and go: ‘you got the right tools mate?’.
“He couldn’t do any more for any person. There was not a malicious bone in his body.”
He added: “What tribute could you pay to somebody who could never meet you without the biggest smile?”
“There is no way that he would have deserved this at all.”
Stuart said he also knew Josh Dunmore, and he was “just such a passionate guy”.
Neighbours near two semi-detached houses cordoned off by detectives in Sutton described hearing shots and seeing armed police arrive soon afterwards.
Detective Inspector Mark Butler, from the major crime unit said officers had been in touch with family and friends of the victims and they were helping the investigation.