The group, consisting mostly of students from Bihar, gathered near the JDU office at Jantar Mantar and sought immediate action from Bihar Police for the safe release of the girl.
Navaruna, 12, went missing from her house in Bihar's Muzaffarpur town since September 18. Bihar Police allegedly did not act saying the girl may have eloped with her lover.
"Navaruna is a girl from our city. 45 days ago she was kidnapped from her home but Bihar police hasn't been able to trace her. They are calling it a case of love affair...And in that pretext they haven't acted," said Abhishek, a Delhi University student from Bihar.
"We came to know about her from Facebook. Students who are studying in various DU colleges will hold protest rallies, demonstrations and write letters to Bihar Chief Minister Nitish Kumar to ensure that Navaruna returns back safely," he said.
Meanwhile, CPI leader D Raja today said law and order in Bihar has deteriorated under the rule of Nitish Kumar.
"He (Kumar) is holding rally today but he must take note that under his rule, law and order has become a serious issue and innocent people are becoming victims of police misbehaviour or lack of serious investigation, so he should take care of these issues," Raja said.