Vijay Shankar Koti, Ashish Bijalwan and Ajay Bhatt were arrested on the basis of the victim's complaint. The fourth accused, Manish Awasthi, is at large, Uttarkashi Police Station in-charge Vinod Thapliyal said.
The police are searching for Awasthi, he said.
They have been booked under relevant sections of IPC, Thapliyal said.
It is suspected that the woman knew one of the accused and was going along with him towards Kuteti. The other three joined the person she was travelling with and committed the crime, he said.