Suspected Islamist Boko Haram gunmen disguised as soldiers mounted a fake checkpoint and killed 19 people near the Nigerian border with Cameroon in Borno state.
The militants dressed in soldiers uniform ordered vehicles that approached the checkpoint to stop and then shot at commuters and drivers yesterday.
Eyewitnesses said several vehicles were stopped and later 19 people were found dead.
Survivors said the attackers later escaped when they were told on phone that soldiers were coming to the highway close to Logumani town where they laid siege.
Three out of Nigeria's 36 states have seen increased attacks by Boko Haram militants since 2009.
Last month, the Islamists killed 50 students of a college of agriculture located in northern Nigeria.
Boko Haram's goal is to install an Islamic government in the north and probably extend to other parts of Nigeria.
President Goodluck Jonathan had declared a state of emergency in Yobe, Borno and Adamawa states where Boko Haram is more prominent.
