Five policemen were yesterday suspended in connection with the matter.
"DSP Ramesh Chandra Joshi has started the probe into the matter and he will submit his report within a week," SP Rajiv Swaroop said.
Aanchal (16), a resident of Chhara village of Uttarkashi, was picked by Tehri Police on the night of May 22 after her maternal uncle had allegedly eloped with a girl of adjoining Tehri district.
Police had come in search of her father Dinesh Rawat. However, when they did not find Rawat and his wife, they took Aanchal along with them.
After remaining in police custody for one night, Aanchal was released next morning and was dropped at her home by the police.
However, within hours of her release, she died.
Angry residents of Purola area had yesterday indulged in arson and demanded stern action against erring policemen.
The post-mortem report of the girl has revealed the cause of death as hanging.
