Parents of dozens of students abducted from a forestry college in Kaduna have been protesting outside the National Assembly, Abuja.
The 39 students were taken from their dormitories in March by gunmen who later released 10 of them.
The protesting families say the authorities are not doing enough to rescue the victims.
The protesters were carrying placards and chanting slogans demanding the authorities to do more to rescue the remaining 29 students, who have been held for nearly two months.
Another set of around 17 students who were kidnapped from Greenfield University also in Kaduna state last month also remain captivity.
There are concerns about their fate after five of the undergraduates were shot dead by their captors.
More than 800 students have been abducted across Nigeria since December by criminal gangs.
Most of them have been released following negotiations between local authorities and the kidnappers.
Ransoms are believed to have been paid.
But Kaduna state government has a policy of non-negotiation with the armed groups, saying such talks only embolden the criminal gangs.
However, efforts by security forces to rescue the captives have so far failed.