Kabul, Afghanistan ? Fighting erupted Wednesday between rival warlords who both claim allegiance to the government of President Hamid Karzai, and an official of one of the warring groups said as many as 60 people were killed and scores more wounded.

A commander for the other side, however, said only three people had been killed in a battle outside the northern city of Mazar-e-Sharif. It was impossible to verify either account.

The fighting came as a deal was signed in the capital of Kabul between the Afghan government and the United Nations that paves the way for teams of U.N. and Afghan personnel to deploy to cities across Afghanistan to start a much-delayed program to disarm militiamen loyal to warlords.

Gen. Abdul Sabur, a spokesman for warlord Atta Mohammed’s Jamiat-e-Islami faction, told The Associated Press by phone that hundreds of rival soldiers were massing around Mazar-e-Sharif.

He said fighters loyal to northern Uzbek commander Abdul Rashid Dostum began battling Atta’s supporters about midday, and the battle continued late into the night.

Sabur said 60 people were killed in that fighting, which involved tanks, heavy artillery and other weapons.

“The fighting is very intense,” Sabur said. “People are very scared. Shops and markets have all closed.”

A second Jamiat spokesman, Ashraf Nadim, said fighters loyal to Dostum launched a separate attack in Maimana city, in the neighboring northern province of Faryab. He said it was not clear how many people had been killed there.

However, Syad Noorulla, one of Dostum’s commanders, told AP that Atta’s forces ambushed his troops about 30 miles west of Mazar-e-Sharif and killed three of his militiamen and wounded four.

He said the situation was tense across the region, but that there was no other fighting.

The two sides have clashed repeatedly in the past two years, though they are nominally both loyal to Karzai’s central government. Countless efforts by the United Nations and the Afghan government to mediate a peaceful resolution have failed.