Two men, aged 22 and 25, have been assaulted on the Garvaghy Road in Portadown, County Armagh.
They were attacked by a group who were carrying weapons at about 04:30 BST on Sunday. The two men received head injuries and are being treated in hospital.
A 50-year-old man has been arrested on suspicion of attempted murder.
Police said that a burned-out car, believed to be related to the assault, was later found on the Drumnagoon Road.
A police cordon was in place on Sunday morning but has now been removed and the road has been reopened.
Keith Haughian of Sinn Féin said he had spoken to police and residents and his understanding was that a “car pulled up and four individuals got out and attacked the men in a serious assault with hammers”.
He said he believed the two men’s mobile phones had also been smashed.
SDLP Councillor Declan McAlinden has condemned the attack
“Residents have woken up to the shocking news that two young lads were assaulted coming home from a night out,” he said.
“It appears to be a random attack, and it’s a worrying attack.
“The people in this community are a proud community, and they absolutely don’t want this kind of activity in the area.”
Upper Bann MLA Jonathan Buckley also voiced his disgust at the attack and said there was “no place for such violence in our community”.