Accused Birbal, who works as a labourer, is a neighbour of the victim. He was arrested from his residence in Harijan Basti in north Delhi, they said.
The incident took place on Monday night at around 8 pm when the victim's parents had gone out for some work, leaving the victim with her two siblings. The victim's father, who also works as a daily labourer, later found her missing, police said.
Birbal lured the girl with a toffee while she was playing outside her residence. He took her to a deserted place near a railway track and raped her near Anand Parbat area. He also tried to kill her by smothering her, police said.
"Birbal dumped the girl in six-feet-deep pit as he saw her unconscious, thinking she had died, and fled the spot," Deputy Commissioner of Police Madhur Verma told IANS.
"Birbal confessed to his crime during interrogation and told police about the location where he had dumped the victim. Police found the girl alive with injury marks. She was admitted to a nearby hospital in critical condition," the DCP added.
A case has been registered against Birbal under the Protection of Children from Sexual Offences Act, 2012 (Posco) at Sarai Rohilla Police Station.
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