Police on Friday arrested a young man for assisting in the rape of an eighth grader girl in Dohar upazila.
The rape suspect and one of his associates are on the run. Police declined to release their names.
Dohar police station's sub-inspector Akhil Ranjan said the 22-year-old rapist had an affair with the 15-year-old victim.
He lured her to a Chinese restaurant in Joypara Bazar on Wednesday and raped her with the assistance of his associates.
When the girl returned home, she informed her mother about her ordeal. Her mother filed a case accusing the three on Wednesday night.
The victim was sent to Sir Salimullah Medical College Hospital on Thursday for medical tests.
"We're trying to arrest the rapist and his associate," the SI said.