rebels in Libya to overthrow Col Muammar Gaddafi in retaliation for the support the late Libyan leader had given to armed groups in Darfur.

At the same time, the Sudanese security forces cracked down on pro-democracy protests in the capital, Khartoum, making sure that they did not threaten Mr Bashir's power.

Now, the Arab League has appointed Gen Dabi, 63, to spearhead the mediation effort in Syria, another Western pariah accused of war crimes.

This has dismayed human rights groups, with Amnesty International warning that it could threaten the credibility of the entire mission.

"The Arab League's decision to appoint as the head of the observer mission a Sudanese general on whose watch severe human rights violations were committed in Sudan risks undermining the League's efforts so far and seriously calls intoquestion the mission's credibility," it said in a statement.

Gen Dabi served as head of the Sudanese directorate of military intelligence when Mr Bashir seized power in a coup in 1989 - a period marked by "arbitrary arrest and detention, enforced disappearance and torture", Amnesty says.

image caption Syrian opposition activists say they have little faith in the Arab League's initiative

His name was also linked with the summary trials and execution of 28 army officers who mounted a failed coup attempt against Mr Bashir in April 1990, an anti-government Sudanese news site, Alrakoba, reports.

After his term as military intelligence chief, Gen Dabi headed Sudan's foreign intelligence agency before returning to the army to serve as the deputy chief of general staff in 1996.

Syrian opposition groups have also expressed concern about