It was unclear if any soldiers were hurt in Tuesday's attack, which was blamed on Boko Haram terrorists, AP reported.
Police deputy superintendent Victor Isuku said preliminary reports indicate that those killed were the driver and passengers in the explosives-laden minivan.
Boko Haram recently has stepped up attacks after a months-long lull caused by a leadership struggle.
The terrorist group has killed more than 20,000 people over several years and forced some 2.6 million people from their homes.