A major police investigation is under way after a man was seriously injured in a stabbing incident in north Belfast that police have described as a critical incident.The attack happened on Kinnaird Avenue shortly after 10:30pm on Monday. According to the Police Service of Northern Ireland (PSNI), officers responding to reports of a stabbing found a man in his 40s with serious injuries. He was taken to hospital for treatment, where he remains under medical care.A man in his 30s was arrested at the scene on suspicion of attempted murder and remains in police custody. Detectives have launched a major investigation to establish the circumstances surrounding the attack and whether any additional individuals were involved.The incident has sparked concern across Northern Ireland after video footage circulated online showing members of the public intervening during the attack.The PSNI said officers and emergency services were called to Kinnaird Avenue shortly after 10:30pm following reports of a serious assault.When police arrived, they found the victim with significant injuries. The area was quickly cordoned off as officers began forensic examinations and door-to-door inquiries. A substantial police presence remained in the area throughout Tuesday as investigators gathered evidence and spoke to witnesses.Police have not disclosed what led to the incident and say inquiries are continuing to establish a motive.Video shared on social media appears to show bystanders stepping in during the attack. Investigators have urged members of the public not to share the footage because of its graphic nature and its potential impact on the ongoing investigation.Assistant Chief Constable Ryan Henderson described the stabbing as a “deeply concerning assault” and confirmed that the PSNI had declared it a critical incident due to its seriousness and the impact it had on the local community.He said detectives were working to establish exactly what happened and reassured residents that community safety remained the force’s priority.Mr Henderson also praised members of the public who intervened during the incident, saying they had shown “incredible bravery and community spirit” in difficult circumstances.The PSNI has appealed for witnesses, as well as anyone with dashcam, CCTV or mobile phone footage, to come forward. Officers have asked anyone with information to quote reference number 1654 of 08/06/26.The stabbing prompted swift condemnation from political leaders in both Northern Ireland and Westminster.Prime Minister Sir Keir Starmer described the scenes as “sickening” and said there could be no tolerance for such violence on UK streets.North Belfast MP John Finucane said he was shocked by the attack and expressed his support for the victim and his family. Other local representatives also voiced concern about the impact on residents and praised those who stepped in to help.Community leaders said many people had been left distressed not only by the incident itself but also by the circulation of graphic footage online.
