The accused, in his 30s, lived on ground floor of the building in east Delhi's Gandhi Nagar in which the victim also stayed, police said, refusing to give any more details about him.
The girl was abducted from outside her house April 15 and raped repeatedly, police said yesterday.
The girl was rescued when her family members said they heard her screams emanating from the accused's flat Wednesday evening, police said.
"The girl was in an unconscious condition when she was rescued from the flat. The accused managed to escape," said a police officer.