New Delhi, Dec 27 : A woman and her 3-year-old son were killed while her four other kids, including a pair of twins born seven days ago, sustained injuries after the roof of their single-storey house in central Delhi collapsed on Tuesday, an official said. The incident happened near the Chitli Qabar area of Jama Masjid. The deceased have been identified as 30 year-old Ruksaar and Alia. According to a senior police official, a call regarding the roof collapse of a house was received at 4.45 a.m. following which a police team rushed to the spot. "There were six persons affected by the fall. Ruksara had come to her father's house with her 5 children," said the police official. "Her children, Abdul, Subhan, Junaid M. and Judera F. are undergoing treatment while Ruksara and Alia were declared brought dead to the hospital by the doctor. Junaid is critical," said the official. The building is around 80 years old and as a precautionary measure, other neighbouring buildings have also been got evacuated. /IANS