They also faulted the Assam Police for "arriving late" to the spot in front of a bar on the Guwahati-Shillong Road on Monday night where the girl was molested.
The footage of the incident which was uploaded on video-sharing website YouTube sent shock waves across the country.
"It is absolute outrage....Because it has happened just 2 km from the seat of governance in Assam. And the fact that if it could happen in a public place, on a public road, for more than 30 minutes and police doesn't come, what is the message?" CPI(M) MP Brinda Karat asked.
"What is the message that goes out from this incident? That women in India are not safe. The second message which goes is that police is not accountable. There has to be prosecution of police officials responsible for this," she said.
Echoing similar views, National Commission of Women chief Mamta Sharma demanded that the police and state authorities take the matter seriously and arrest all those responsible for the incident.
"This could have happened anywhere else and these people should be punished as it is a very serious offence," she said.
More From This Section
Congress MP and former NCW chief Girija Vyas said not only Assam, but all other states should also look into the seriousness of the matter because "mentalities" have not changed.
"Every girl has the right to attend a party. She was molested by a group of boys immediately after she left the party," she said.