Nigerian troops were forced to retreat from Boko Haram's Sambisa Forest stronghold in the restive north-east after a landmine blast killed one soldier and three vigilantes, security sources said Thursday. Military top brass said on Wednesday that soldiers were conducting offensives "in some forest locations" in the area after it was announced last week that operations were imminent.
The Sambisa Forest is located in the state of Borno, some 80 kilometres (50 miles) from the town of Chibok, from where more than 200 schoolgirls were kidnapped in April last year. It has been claimed the 219 schoolgirls still being held were initially kept in the former game reserve, although others have said they may have been split up and moved to Chad or Cameroon. Defence spokesman Chris Olukolade said in a statement that a senior Boko Haram commander was killed, as well as a number of militants who attacked a patrol.