Nigerian government forces have rescued another 1,880 hostages from the den of the terror group Boko Haram, the army authorities said on Thursday.

The hostages, all women and children, were freed from inside the Sambisa Forest, known as the largest training camp of Boko Haram in the country's northeastern Borno region.

The troops also arrested 504 Boko Haram terrorists, of whom 19 willingly surrendered, Borno Combatant Commander Lucky Irabor told Xinhua news agency. 

The army has started constructing roads leading to the Sambisa Forest to ease troops' operations in mopping up Boko Haram fighters in their den.