The UN Security Council has passed a resolution imposing sanctions against four Sudanese nationals accused of war crimes in Sudan's Darfur region.
Civilians described attacks by government aircraft and militiamen
The four include two rebel leaders, a former Sudanese air force chief, and the leader of a pro-government militia, accused of widespread atrocities.
In Darfur itself, a BBC correspondent has found evidence of continuing attacks on civilians by militias.
Violence in Darfur has killed some 100,000 people and created 2m refugees.
Last week, the top UN aid official said the humanitarian situation in Darfur was as bad as when the conflict came to the world's attention in 2004.
The BBC's Orla Guerin in Darfur met streams of civilians who said they were fleeing their remote village of Jogana.
They said they had been attacked by government aircraft and militiamen that were fighting rebel forces in the area.
Our correspondent said she could hear the sound of bombing from 40km (25 miles) away.
African Union (AU) peacekeepers met the civilians and gave them water but did not intervene in the fighting.
'Tough to enforce'
The UN resolution was sponsored by the US, which says a genocide is being committed against black Africans in Darfur.
WAR CRIMES SUSPECTS
Adam Yacub Shant
rebel SLA commander
Gabril Abdul Kareem Badri
rebel National Movement for Reform and Development field commander
Gaffar Mohamed Elhassan
ex Sudan Airforce commander
Sheikh Musa Hilal
Janjaweed militia leader (pictured)
The war crimes suspects - Adam Yacub Shant, Gabril Abdul Kareem Badri, Gaffar Mohamed Elhassan and Sheikh Musa Hilal - would be subject to a ban on foreign travel and have any assets held abroad frozen.
The BBC's correspondent at the UN headquarters in New York, Laura Trevelyan, said it had taken weeks to get to this point and the sanctions could be difficult to enforce.
Russia and China, both permanent members of the Security Council with the power to veto the resolution, had initially opposed this move, but chose to abstain because the African nations supported the sanctions.
This is the first time those involved in Darfur's atrocities have been directly targeted.
However the BBC's Jonah Fisher in the Sudanese capital, Khartoum, says the effect of the sanctions will be more psychological than physical.
Sudan's governments has consistently said the scale of the problem in Darfur is being exaggerated for political reasons.
It denies backing the Arab Janjaweed militias accused of mass rape, killing and looting.
The UN is also considering taking control of the peace mission from the cash-strapped AU.
Sudan opposes such moves, saying extra funding should instead be given to the 7,000 hard-pressed AU peacekeepers already in Darfur.
The AU is also sponsoring peace talks between the government and rebels and has set a deadline of 30 April for the two sides to reach a deal.
Its chief mediator Salim Ahmed Salim is hopeful that representatives of the government and one of the Darfur rebel groups attending negotiations in the Nigerian capital, Abuja, will agree to the peace plan.
"The proposals are comprehensive and in our opinion they constitute a sound basis for a solution to the crisis," he told the BBC's Network Africa programme.
The draft deal addresses the issues of power-sharing, wealth-sharing, security arrangements and the implementation of a comprehensive ceasefire, he said.
"Our challenge has been to try and narrow the gap, and that we have done. Now the challenge is up to the leaders themselves," he said.