An 18-year-old man is critically ill in hospital following a stabbing in west Belfast on Sunday morning.
The incident took place in the Cullingtree Road area of Divis around 6am.
On Sunday afternoon police arrested a 31-year-old man after a 30-year-old man was stabbed in Killuney Drive, Armagh.
It was the sixth stabbing reported to the PSNI since Thursday, with others taking place in Belfast city centre, Armagh city and Ballymena.
A previous stabbing incident took place at Corrigan’s Court, Armagh around 2.15am on Saturday when a 24-year-old man was assaulted by two men.
His injuries are not believed to be life-threatening. A 27-year-old man has been arrested.
A man and a woman, both aged 23, were arrested by police investigating the stabbing in Ballymena on Thursday but later released on bail.
The 30-year-old victim was located in a flat in the Waveney Road area around 1pm and taken to hospital where his condition was described as “stable”.
Also on Thursday, a man in his 30s, was attacked in the Hawthorn Street area of west Belfast around 1.40pm.
On Thursday evening another man was stabbed in Belfast’s High Street, leading to a 23-year-old man being charged with attempted murder and possession of drugs.
Commenting on the latest attack in west Belfast, SDLP MLA Alex Attwood said it was “truly appalling”.
“The man suffered knife wounds which have left him in a serious condition in hospital. This is the second attack of this nature to have happened in west Belfast in recent days.”
Mr Attwood said there is “growing concern about the rise in knife crime attacks in Belfast,” and added: “Any level of knife crime is unacceptable, and more needs to be done to deal with knife crime in our society. I would appeal to anyone who has any information relating to this attack to contact the police.”
Sinn Féin councillor Mary McConville has said: “This recent stabbing which has left a young a man fighting for his life brings home the reality of these incidents.
“The young man has suffered knife wounds leaving him in a serious condition and his family traumatised.
“More needs to be done to deal with the growing knife crime in our society and I am calling on young people not to be drawn into carrying knives.
“I would call on people who have any information to pass it on to the PSNI.”