Nigeria student kidnapping near Kaduna army base
Gunmen have abducted dozens of students from a college in the northern Nigerian state of Kaduna, authorities say.
The attackers stormed the institution in the town of Mando overnight.
State authorities say that 180 students and staff were rescued by the Nigerian army in the early hours of Friday, but about 30 students remain missing.
It is not yet clear who was behind the raid on the Federal College of Forestry Mechanisation, which is located near a military training academy.
About 800 students have been seized since December in several raids on schools in northern Nigeria. They have all been released after negotiations with the gunmen.
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Parents and relatives gathered at the college on Friday morning to wait for news on the fate of their children.
Some residents said when they heard the kidnappers' gunfire overnight at the college, they thought it was a military exercise at the military institution.
Witnesses say when the military arrived in the school compound, the attackers had left. Now troops with tanks and helicopters have been deployed to try to rescue the abductees.
The BBC's Ishaq Khalid in Abuja say this is the first such attack on a college on the outskirts of a major city - most previous abductions from schools happened in remote areas.
Our reporter says the audacious attack so close to a military site comes as an embarrassment for the Nigerian authorities, who keep assuring citizens they are trying to tackle the county's insecurity.
Both the federal government and the Kaduna state government say they are averse to negotiations with armed gangs, our reporter adds, many of whom profit from weak security infrastructure through ransom payments after kidnappings.
A recent report released by Kaduna state authorities said nearly 3,000 people in the state were killed or abducted by criminal gangs last year.
This week, neighbouring Niger state announced it was shutting all secondary schools for a fortnight for "risk assessments". Three other northern states - Kano, Yobe and Katsina - have also shut some secondary schools.
Recent school kidnappings in Nigeria:
26 February - 279 schoolgirls seized in Jangebe, Zamfara state
17 February - One pupil killed; 42 staff, students and family members taken from Kagara, Niger state
25 January - Gunmen kidnap seven children from an orphanage in the capital, Abuja
19 December - More than 80 schoolchildren kidnapped from Mahuta village, Katsina state
11 December - More than 300 boys abducted from a school in Kankara, Katsina state
All have since been freed.