Authorities in north-eastern Nigeria have begun digging a 17 mile trench around the University of Maiduguri to prevent attacks by Boko Haram Islamist militants.
On Sunday three suicide bombers attacked the university killing themselves and a security guard.
Nigerian police say that in the first attack on Sunday, a suicide bomber blew himself up inside the grounds of Maiduguri’s university, killing a female security guard.
Minutes later, four female suicide bombers then attacked two villages just outside the city, killing 12 people.
According to BBC News, the trenches are designed to make it impossible for the militants to drive into the university as well as making it harder for them to access the campus on foot.