ABUJA, Nigeria — A shootout between extremists and Nigerian security forces rocked the nation's capital early Friday, according to a Nigerian security official. It is the first violence from the radicals of Boko Haram in Abuja this year and highlights Nigeria's continuing security problems from the extremists. The gunfight in the capital occurred as Nigerian officials were recovering bodies in Benisheik, in northern Nigeria, where 143 civilians were killed by suspected Boko Haram fighters. The killings in Benisheik took place on Tuesday and represent one of the highest death tolls in the Islamic uprising in northeast Nigeria. Together the gunfight in the capital and the mass killings in the northeast challenge the Nigerian military's insistence that it is winning the war against the extremists since a state of emergency was declared May 14. The radicals of Boko Haram want to enforce strict Shariah law throughout Nigeria, Africa's most populous nation of more than 160 million people almost equally divided between Muslims and Christians. Boko Haram is blamed for violent attacks that have killed nearly 2,000 in Nigeria since 2011. The shooting in the capital broke out early Friday when a security team was searching for hidden weapons and it was fired upon by members of Boko Haram, said a statement issued Friday by Marilyn Ogar, Deputy Director of the Department of State Services. Two arrested members of Boko Haram had led a security team in Abuja to a site near the residential compound for legislators where they said arms were buried, said Ogar. “No sooner had the team commenced digging for the arms than they came under heavy gunfire attack by other Boko Haram elections,” said Ogar's statement. Some people were injured but did not say there had been any deaths, she said. She said 12 people were arrested. Boko Haram's violence occurs mostly in Nigeria's northern areas although there have been some serious incidents in the capital. In August 2011 a Boko Haram suicide car bomb exploded at the United Nations offices in Abuja, killing 24 people. In April 2012 the Abuja office of the newspaper, This Day, was hit by a car bomb and two people were killed. In northeastern Nigeria, officials on Thursday recovered 143 bodies in the town of Benisheik after an attack on Tuesday by a large, heavily armed group suspected to be Boko Haram. Two soldiers and three police officers also were killed, according to a soldier who spoke to The Associated Press on condition of anonymity because he was not authorized to speak to the press. The private said extremists disguised in military fatigues attacked in about 20 pickup trucks and two light tanks firing anti-aircraft guns that overwhelmed soldiers armed only with automatic rifles and rocket-propelled grenades. “We had to retreat to our base to reinforce after running out of ammunition. We had to run for our lives,” said the private, who said he hid in a millet plantation. “But they followed us down and surrounded our base and began to shell our building. We couldn't stand the heat of their superior firepower. We had to retreat into the village after they killed two of our soldiers and three policemen.” He said the attackers finally retreated in triumph, taking off with an additional four military patrol trucks and two light armored tanks. An AP reporter watched as Environmental Department workers piled corpses swollen by the tropical heat into trucks at the near-deserted village where hundreds of homes had been torched. “We have been picking corpses off the roadsides all day, there are more in the bush ... We have so far picked up 143 corpses,” said Abdulazeez Kolomi, an assistant at the Environmental Protection Agency. — AP