Chadian soldiers, part of a multinational force appointed by the African Union to help Nigeria fight Boko Haram, clashed with the insurgents in the town of Gamboru in Borno State near the border with Cameroon, according to a statement issued by Chad's army and read on the Nigerian Television Authority.
"We destroyed 13 pickup trucks and dozens of motorcycles that were used in the attack," the statement said.
Last week, the Chadian army said it killed 117 Boko Haram insurgents when it recaptured the town of Dikwa, also in Borno State.
The rebels control towns in north-eastern Nigeria spread over an area the size of Belgium and have killed more than 13,000 people since 2009.
Boko Haram, which seeks to establish a state with its strict interpretation of Islamic law, has expanded its violence into three of Nigeria's neighbours - Cameroon, Niger and Chad.
