Somalia’s warlords have agreed to disarm and join a new national army, a government official said on Friday. But violence in the capital the same day brought home the challenge of restoring order and establishing real authority in this fractious and heavily armed country.The announcement followed a meeting between President Abdullahi Yusuf and clan warlords that proceeded even as, just outside, clan gunmen fired a rocket-propelled grenade and briefly exchanged gunfire with government troops. The fighting, which one fighter said was sparked by a dispute over where to park an armoured car, left at least six dead and 10 wounded.Besides clan divisions, resentment of Ethiopia’s intervention and remnants of the Islamic movement also were likely to bedevil the government for some time to come.“The warlords and the government have agreed to collaborate for the restoration of peace in Somalia,” said government spokesman Abdirahman Dinari.Yusuf had met with three top Somali warlords and two other faction leaders, the spokesman said.“The agreement means they have to disarm their militia and their men have to join the national army,” Dinari told The Associated Press.One of Somalia’s most powerful warlords, Mohamed Qanyare Afrah, told the AP after the meeting the war lords were “fed up” with guns and ready to cooperate with the government. However, another warlord spelled out a warning. “If the government is ready to reconcile its people and chooses the right leadership, I hope there is no need to revolt against it,” said Muse Sudi Yalahow, whose fighters control north Mogadishu.