Officers were called to Mill Pond Road at about 11.45pm, after a man was stabbed.
The victim – who is said to be middle-aged – was stabbed in the left leg and approached a nearby house for help.
One resident rushed to help the man after the victim stumbled into their front door.
Wishing to remain anonymous, the resident, who is trained in first aid, said: ‘I heard him screaming for help, he was losing a lot of blood.
‘After I saw him I grabbed my first aid kit and dialled 999 – I stayed with him for about 45 minutes.
‘He was in a very bad way, he went into shock and was going in and out of consciousness.’
Police have not yet confirmed details.