Several people were injured during a clash between two student groups at the Chaura Maidan, police said on Tuesday.
Superintendent of Police (Shimla) Sanjeev Kumar Gandhi told PTI that several people were injured when a scuffle broke out between the Students' Federation of India (SFI) and the RSS-affiliated Akhil Bharatiya Vidyarthi Parishad (ABVP) near the Cecil hotel.
In a statement, the SFI's Shimla District Committee said students affiliated with the ABVP attacked its members with sharp weapons.
"The ABVP launched the attack on the SFI members as they have been been raising their voices on several issues, including two women being paraded naked by a mob in strife-torn Manipur and the recruitment of teachers and employees aligned with the RSS at Himachal Pradesh University," the CPI(M)-backed organisation said in its statement.
The SFI warned that the organisation will launch an aggressive agitation if those involved in the attack are not booked.
ABVP leaders, however, claimed that students affiliated with the SFI obstructed their way near the Cecil, a hotel in the Chaura Maidan area, and abused them before assaulting them with sharp weapons.
Condemning the incident, the ABVP's Kotshera College unit chief Sushil Sharma said the SFI has a history of violence and frequently indulges in such acts.
Superintendent of Police Gandhi said medical examination of the injured students is being done and an FIR has been registered against 10-12 people under sections of the Indian Penal Code.
Both the students' organisations have demanded strict action against those involved.