The victim, a student of class XI in her complaint said, she had gone out to relieve herself on the night of July 25, when two youths took her away to a school, where two others joined them later, Superintendent of Police, Subhash Chand Pandey said.
The girl in her statement has said that the four accused fed her some intoxicating substance and then gang-raped her, the SP said, adding the next day she was admitted to a nearby hospital by her family, from where she was shifted to the district hospital here last night in a serious condition.
Following her complaint, an FIR was lodged against the four persons including the son of the MP, police said.
The incident took place in Koirauna police station area.
Raids are being carried out to nab the culprits, police said.