The blast, which occurred around 8 p.m. Tuesday, appears to have originated with an explosive hidden in a motorized rickshaw outside the facility.
Yobe state police commissioner Sanusi Ruf'ai told CNN that it was "too early" to provide details about casualties, though
Yobe, a state in the turbulent northeastern portion of Nigeria, has been subject to attacks from the Boko Haram militant group.
Notable deaths of 2014 [PHOTOS]
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