A man has been left in a serious condition in hospital after being attacked in Ballymena yesterday.
Another five people were attacked during a separate incident in Downpatrick, and a woman was threatened at gunpoint during a hijacking, police have said.
At 6am yesterday a man in Ballymena was viciously attacked by another male at a garage forecourt in the North Road area of the town.
After the alarm was raised the victim was taken to hospital where his injuries have been described as serious.
Police said the man's attacker is thought to have been wearing a distinctive white T-shirt, which he may have discarded somewhere in the area after the attack.
Police have asked anyone who finds a white T-shirt in the area not to touch it, but to contact them immediately.
A short time after the attack a 23-year-old man was arrested in connection with the incident. He has been assisting police with their inquiries.
In an attack in Downpatrick shortly after 1am yesterday a group of up to five people were assaulted by two men during an incident in the Ballynoe Road area.
The injuries of the victims are not believed to be life-threatening.
Two men, aged 32 and 33, have been arrested and are helping officers with their inquiries, a police spokesman said. Officers are keen to speak to anyone who may have witnessed the attack.
Meanwhile, in north Belfast a woman was threatened at gunpoint during a hijacking in the Downview Park area on Boxing Day.
Shortly before 11.30pm the woman was sitting in her car when a masked man approached. The man, who was wearing a dark hooded top, balaclava and gloves, opened her door and pointed a firearm at her before stealing her car.
The woman is not believed to have been hurt during the incident, but was left shaken.
Anyone who may know the whereabouts of the stolen blue Renault Megane car, registration number AEZ 2359, has been asked to contact police.
Information about any of the incidents can be passed on to police on 0845 600 8000.