Nov 16 (Reuters) - Congolese rebel leader Laurent Nkunda agreed on Sunday to support a peace process for eastern Congo being negotiated by United Nations envoy Olusegun Obasanjo.

Tutsi insurgents loyal to renegade General Nkunda had launched a major offensive on Oct. 26, advancing to within 20 km (12 miles) of Goma.

Here are some details about the conflict in eastern Congo.

* RENEWED CONFLICT:

-- Weeks of fighting worsened an already dire humanitarian crisis in North Kivu, which had 850,000 internal refugees even before the most recent fighting began in August, according to U.N. figures. Since then, 250,000 people have been forced to flee, many of whom have been displaced several times.

-- In August, Nkunda's rebels suspended participation in the tenuous peace process, killing off a frequently broken ceasefire dating back to a January 2008 peace deal.

-- Nkunda's rebels and government troops each accused the other of provoking clashes. The U.N. peacekeeping operation, MONUC, blamed Nkunda's troops for instigating most of the recent fighting and called on eastern rebel and militia groups to abide by the January peace agreement. Nkunda accuses MONUC of bias.

-- Obasanjo, who held talks on Saturday with Congolese President Joseph Kabila, was seeking to prevent the fighting in North Kivu from escalating into a repeat of the wider 1998-2003 Congo war that sucked in six neighbouring states.

* FAILED CEASEFIRES:

-- A month after the Rwandan-brokered January 2007 peace deal collapsed, U.N. mediators announced a limited ceasefire on Sept. 6, 2007 after two weeks of fighting in North Kivu province.

-- Nkunda, who made parts of North Kivu province into his personal fiefdom, later said he was abandoning the ceasefire because of attacks by the government, which in turn accused him of pushing the country towards war.

-- Fresh talks opened in January 2008 in Goma. On Jan. 23 nearly two dozen rebel and militia movements signed the peace accord with Congo's government to end a decade of conflict in North and South Kivu. The deal, brokered by the United Nations and Western diplomats, was plagued by almost daily ceasefire violations from the start and fell apart by mid-2008.

* WHAT ARE THE ORIGINS OF THE CONFLICT?

-- The roots of Nkunda's rebellion lie in unresolved ethnic and political tensions that make racially mixed eastern Democratic Republic of Congo a tinderbox.

-- The region is rich in minerals, such as coltan which is used in mobile phones, making control of the remote terrain, far from Congo's capital Kinshasa, lucrative.

-- The presence in east Congo of both Tutsi and Hutu rebels stems from Rwanda's 1994 genocide, in which 800,000 Tutsis and moderate Hutus were killed in 100 days by the Hutu-led government and ethnic militias.

-- Hutu militias fled to Congo, their presence provoking Tutsi-led Rwandan invasions that helped ignite Congo's wider 1998-2003 war. The war and an ensuing humanitarian crisis have killed some 5.4 million people, most through hunger and disease.

-- Nkunda led a revolt in 2004 with 4,000 soldiers and briefly captured the South Kivu capital Bukavu. An international arrest warrant was issued for him for war crimes committed while occupying Bukavu, but Congolese officials say this has expired.

-- After 2006 polls aimed at drawing a line under the war, President Joseph Kabila pledged to bring peace to Congo's east.

-- Nkunda has said he was fighting to protect his Tutsi people in eastern Congo against attacks by the Democratic Forces for the Liberation of Rwanda (FDLR), a Rwandan Hutu rebel group which controls parts of North Kivu. He says Kabila's government backs the FDLR, a charge the government denies.

-- The FDLR includes Rwandan ex-soldiers and members of Hutu Interahamwe militias which took part in the Rwandan genocide.

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