Mohali, June 27 -- An 18-year-old youth was killed and his friend critically injured after a group of assailants allegedly attacked them with swords and knives inside an abandoned building near Nayagaon bridge late on Thursday night. Police said the attack appears to have stemmed from previous enmity between two groups. The deceased was identified as Karan, an electrician and resident of Khuda Alisher, Chandigarh. His friend, Harpreet Singh, remains hospitalised. According to police, the attack occurred around 10.30 pm inside a dilapidated building that residents say has long been used by youngsters for drug abuse and other illegal activities. Prima facie, an argument broke out among a group of youngsters before it escalated into the assault. Police said Karan suffered around 12 wounds on his stomach, neck, arms and face, while Harpreet sustained deep injuries to his neck. Station house officer (SHO) Shivdeep Brar said some of the accused were allegedly under the influence of intoxicants at the time of the incident. "Preliminary investigation suggests the attack was the result of previous enmity between the two groups. Both the deceased and the accused have criminal cases registered against them. Multiple accused were involved in the attack, and teams are working to identify and arrest all of them," he said. According to Karan's brother, Harendra, the victim had left home around 9.30 pm. When he did not respond to repeated phone calls, family members began looking for him. They later reached Nayagaon, where residents informed them that two youths had been attacked. The family found Karan lying in a pool of blood and rushed him and Harpreet to the Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh. Doctors declared Karan dead on arrival, while Harpreet was admitted for treatment. Karan's mother demanded the arrest of all those involved and alleged that police had failed to act effectively. The SHO said a case has been registered and efforts are on to arrest the accused....