* Khartoum forces still attacking Darfur civilians
* UN rights investigator also concerned at killings in south
* Mandate of Sima Samar on line at Human Rights Council
By Stephanie Nebehay
GENEVA, June 16 (Reuters) - The U.N. human rights investigator for Sudan said on Tuesday that Khartoum’s forces continue to carry out land and air attacks on civilians in Darfur, and arrest and torture activists and aid workers there.
Sima Samar, U.N. special rapporteur on human rights in the Sudan, also voiced concern at "large scale killings" in the south, where several hundred civilians died in inter-tribal clashes in March and April amid growing violence in the region.
But diplomats said Sudan was trying at the United Nations Human Rights Council this week to win backing from African and Islamic states to block Western attempts to extend her mandate to report on violations in Sudan for a further year.
"I continue to receive reports of arbitrary arrests, detention, as well as allegations of ill-treatment and torture of human rights defenders and humanitarian workers by security forces," the former Afghan deputy prime minister told the 47-member forum.
Her latest report, covering from last August to her visit to Sudan earlier this month, was also issued on Tuesday. "Land and air attacks by government forces on civilians in Darfur took place during the reporting period," it said.
Air attacks in Darfur are banned under U.N. Security Council resolutions and failed ceasefires, but Khartoum has in the past reserved the right to attack the Justice and Equality Movement and other rebels who did not sign a 2006 Darfur peace deal.
The United Nations says six years of conflict have killed up to 300,000 people and uprooted more than 2.7 million in Darfur. Khartoum says 10,000 people have died.
The International Criminal Court has issued an arrest warrant for President Omar Hassan al-Bashir on Darfur war crimes charges.
All sides in Darfur have committed alleged killings, torture, and sexual violence against women and children, Samar said. Three peacekeepers have been killed during the period.
Fighting in South Darfur in January between the army and rebel forces was marked by "ground offensives and indiscriminate aerial bombardments by government forces in some instances, which failed to distinguish civilian communities, properties and objects from military targets", according to her report.
But Abdel Daiem Zumrawi, under-secretary at Sudan’s justice ministry, dismissed her speech and 22-page report, charging that they "failed to give a true picture of human rights in Sudan".
Her mandate, established in 1993, was based on "legacy", and magnified weaknesses rather than progress, he told the council.
Samar’s mandate is set to expire when the council’s three-week session ends on Thursday.
The European Union is trying to salvage the mandate, one of eight remaining U.N. rights investigators assigned a specific country. In recent years the council has dropped its investigators on the Democratic Republic of Congo, Cuba, Belarus and Liberia.
"They have to acknowledge their problems. The denials of the problem is not going to help," Samar said of Sudan’s government.
Asked why her mandate should be retained, she said, "It’s a bridge between the international community and that country, first of all. Secondly, I think it is a voice for the voiceless people who are living under difficult circumstances." (Editing by Louise Ireland)