Kano, Nigeria (Wikimedia Commons)

Kano state police spokesman Ibrahim Idris said the attackers targeted a section of Bayero University's campus where religious groups use a theater and other areas to organize worship services. Officials have not confirmed the official number of casualties, but six others were in serious condition.

"Reports say that they came in one vehicle and they also came on the bike and started shooting sporadically and at the same time threw about four or five small locally made bombs," journalist Salihu Tanko told CNN.

Tanko said the attack happened while the university is on a break so most of the students are not on campus.

One witness told AFP news agency the attackers had first thrown in explosives and fired shots, "causing a stampede among worshippers," according to the BBC.

No group has claimed responsibility for the shootings, but Idris said the attackers packed small explosives inside of aluminum soda cans, a method previously utilized by a radical Islamist sect known as Boko Haram, according to the AP.

Nigeria's government has struggled to thwart attacks from the militant group, which operates in the country's Muslim north, but has struck as far south as the capital city of Abuja.

The group's assault on government buildings and other sites around Kano back in January left at least 185 people dead. Boko Haram has been blamed for attacking police stations and orchestrating small-scale assaults throughout the city.

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