Relatives carry for burial the body a policeman killed in the November 4 attacks in Damaturu, Yobe State, northeastern Nigeria, on November 7, 2011. Nigeria was on high alert Monday after the United States warned of fresh attacks following a wave of deadly blasts claimed by Islamists killed 150 people in the northeast of the country. The November 4 attacks in the city of Damaturu were among the deadliest ever carried out by Boko Haram, an Islamist sect based in the north of Africa's most populous country. AFP PHOTO / PIUS UTOMI EKPEI (Photo credit should read PIUS UTOMI EKPEI/AFP/Getty Images)
