A teenager stabbed to death at home in front of his parents may have been the victim of mistaken identity, police have said.
Aamir Siddiqi, 17, was killed after opening the door to two masked men at his home in Cardiff. His parents, aged 55 and 68, were also stabbed by the attackers as they rushed to help their teenage son on Sunday afternoon.
Both suffered serious stab wounds to the torso as they tried to fight off the two men. Both were taken to hospital for treatment and have since been released.
Nishat Siddiqi, 34, one of the teenager's three sisters, appealed to the public to come forward with any information, saying: "We are afraid in our own family that the people who committed this crime may do so again. Please help so that these perpetrators are found before they harm anyone else."
Detective Chief Superintendent Stuart McKenzie, who is leading the investigation, said: "He was an upstanding member of the community. He was an avid sports fan and scheduled to go to university in the autumn. We have no motive.
"One hypothesis is that Aamir was mistakenly targeted. We cannot understand why he was targeted."
He added that there was also no evidence that the attack was in any way racially motivated.
Two men of Asian appearance were seen leaving the area soon after the stabbing and were seen to be pulling black knitted balaclavas over their faces.
