A six-year-old boy in Karnal district was locked up in a dark room by his kindergarten teacher for not doing his homework and died of trauma one-and-a-half months later, police said on Tuesday after receiving a complaint from his family. The LKG student, Pankaj, died at the Post-Graduate Institute of Medical Sciences (PGIMS) in Rohtak on Sunday night where he was admitted last month. In its complaint to Karnal police, the family of the victim alleged that Pankaj was traumatised by the punishment given to him by his teacher at the Rajkul government school near Gharounda town. The teacher had allegedly punished the small boy by locking him inside a dark room of the school on Dec.27 for not doing his homework. After the school got over, the teacher left the campus and the boy was found unconscious by his elder brother who came looking for him inside the locked room. Suffering from trauma, the boy stopped eating properly and soon fell ill. He was taken to hospital and later brought to PGIMS Rohtak where he died on Sunday, family members said. \"We are seeking action against the teacher and school authorities. How can a small boy be treated like this simply for not doing his homework,\" asked Dilbagh Singh, a relative. A police official in Karnal said a complaint had been received from the family and investigations were on.