Police in India's southern state of Kerala faced stone-throwing protesters demanding justice over the rape, murder and mutilation of a woman as authorities hunted for the perpetrator of the crime.
Authorities released a sketch of a suspect and said they were looking for a man seen leaving the home of the 30-year-old law student. The victim, from a lower caste, was found by her mother in a pool of blood last week.
Doctors said she had suffered multiple stab wounds and her intestines were pulled out in the April 28 attack in Perumbavoor, 250 km (155 miles) northwest of state capital Thiruvananthapuram.
Police questioned seven suspects on Wednesday but no arrests were made.
Scores of police, some carrying riot shields, were deployed as protesters marched to Perumbavoor's police headquarters. Police baton-charged the crowd as a group of protesters tried to break into the police chief's office.
"We can understand that people are very angry but we have very little evidence to find the accused," said Additional Director General of Police K. Padmakumar. "We are doing our best."
The case has evoked comparisons in the media with the gang rape and torture of a 23-year-old woman in New Delhi in 2012, which sparked nationwide protests.
India toughened its anti-rape laws in response to the outcry following the 2012 murder, but rape, acid attacks, domestic violence and molestation are common.
Reports of a second alleged gang-rape of a 19-year-old student triggered fresh outrage in the state that is in the midst of an election for a new state assembly.
The rape cases quickly turned into a political issue as local leaders demanded an investigation. Kerala's Chief Minister Oommen Chandy, fighting to retain power, said he would introduce new anti-rape rules to avoid lapses in investigations.