Shopkeepers shut shops in Theog town to express solidarity with the victim's family.
The protesters blocked National Highway-5 (NH-5), which links Shimla with upper Shimla district, for several hours. They also surrounded the police station where Superintendent of Police D W Negi was present and broke windowpanes of his official car.
"We demand the case be handed over to the Central Bureau of Investigation. We want assurance from the Chief Minister (Virbhadra Singh)," an uncle of the victim told reporters.
He said police remained silent on the gang rape and murder case for 10 days and all of a sudden announced the arrest of five more accused on Thursday.
"We have doubts the real accused are still roaming free," a protestor said.
In a related development, Inspector General of Police Zahur H. Zaidi, heading a Special Investigation Team (SIT) formed to probe the case, went on leave on Friday.
Over a week after the crime, Director General of Police Somesh Goyal on Thursday said the police had arrested all six accused.
"One accused was arrested yesterday (Wednesday) and five others arrested today (Thursday) in the rape and murder of a girl in Kotkhai (in Shimla district)," he told reporters.
The accused, aged between 19 and 42, included two persons from Nepal and two persons from Uttarakhand, mainly farm labourers settled in Kotkhai area, where the crime happened.
The 16 year old girl was offered a lift in a vehicle by the accused on July 4 when she was returning home from school. On the way, the accused raped and murdered her in a nearby forest. Her body was found two days later.
The arrested persons are prime accused Rajinder Singh, who offered her the lift, Ashish Chauhan, Subhash Bisht, Deepak Kumar, Surat Singh and Lokjan.
The police said the prime accused had developed familiarity with the victim as he offered her a lift twice earlier.