The dead included four officers and five insurgents.
The late night attack occurred in the Babban Gida village of Yobe state, an area consistently under assault by Boko Haram, the Islamist group blamed for killing hundreds in northern and central Nigeria over the past four years.
Yobe state police chief Alhaji Sanusi Rufai told journalists, "They came to attack our station there early this morning at about 01:00 and our men engaged them in a shootout. We killed five of them but they fled with the corpses. Unfortunately, we also lost four of our policemen," News24 news agency reported on Friday. Rufai implied that Boko Haram militants were behind the assault.
Despite the ongoing unrest, last week the Nigerian president's office said that it would consider whether an amnesty for the Islamists could help curb the unrest and end the spiraling violence.