A man remains in a critical condition today (Friday) after being attacked in the street by a man with a metal bar.
The victim, 47-year-old Neil Markland from Tyldesley, was hit over the head after he had been seen possibly tampering with a car.
It happened shortly after 8.30pm on Wednesday, when the victim was walking home along Henry Street, Tyldesley.
The man was inebriated and was spotted by a passerby, a 54-year-old man, who decided to help him walk home.
As they walked by a Vauxhall Astra parked on Henry Street, the victim approached the car and attempted to tamper with the door.
A couple emerged from a nearby house and remonstrated with him.
Fearing a confrontation the passerby called the police and while he was still on the phone, another man arrived and immediately attacked the victim with a metal bar.
He hit him twice over the head, leaving him with serious head injuries.
The offender then walked off.
Officers arrived at the scene within minutes and the victim was taken to Hope Hospital by ambulance. He is now in a serious condition.
Anthony McGill, aged 45, of Tyldesley has been arrested on suspicion of wounding with intent and remains in custody for questioning.
A man and a woman were also both arrested on suspicion of assisting an offender.
Detective Inspector Martin Reddington, of Wigan CID, said: "At first glance this could appear like someone defending property but I want to make it absolutely clear that the violence used was completely disproportionate.
"To attack someone with a metal bar, leaving him with life-threatening injuries, is completely unacceptable.
"This was an attack on a man who was clearly vulnerable through drink.
"I understand this will cause some genuine concern in the community, but I want to reassure people that we have made some quick arrests and we are building up a good picture of what happened.
"However, if anyone we have yet to speak to saw what happened I would ask them to call us."
Anyone with information is asked to call Wigan CID on 0161 856 7252 or Crimsetoppers on 0800 555 111.