New Delhi: An eight-month-old baby girl was sexually assaulted by her cousin in the national capital, police said on Monday, adding that the accused had been arrested.

The police said the incident occurred on Sunday when the baby's parents had been off to their work places and left her with other family members in west Delhi's Shakurpur Basti.

"The victim's family stays on the first floor of their house and the other family members on the ground floor in Shakurpur Basti. Accused Suraj, 28, who is a cousin of the child, took her to other part of the building on the pretext of playing with her and sexually assaulted her," a senior police officer said.

"When her mother, who works as a maid in the area, returned home, she found her daughter unconscious lying in a pool of blood. She informed her husband, who is a manual labourer. They took her to a hospital and informed the police," he said.

"During investigation, Suraj turned out to be the prime suspect. After he was grilled, he fled the home. This confirmed their suspicion of his involvement in the crime. He was later traced and arrested," he added.

The baby suffered severe injuries in her vital organs and was undergoing treatment at a hospital, he added.

"Now Suraj has confessed his crime. The family used to leave the baby at home with cousins and other family members while going for work. A case has been registered against Suraj under the provisions of POSCO," the officer added.