Nairobi/N'Djamena - Chad closed its border with Sudan overnight and severed all economic ties with its neighbour amid accusations of aggression from Khartoum, news reports said Tuesday. A Chadian diplomat accused Sudan of looking for excuses to launch an attack on Chadian territory in a report carried by the BBC.
Sudan had cut off diplomatic ties with Chad on Sunday, accusing N'Djamena of supporting rebels in the crisis-torn western Sudanese province of Darfur.
The Human Rights Watch organization expressed concern Tuesday at mass arrests in Khartoum after a rebel attack on the suburbs. At least 300 people have been arrested on suspicion of cooperating with the rebels since Monday, state media reported.
"Given Khartoum's record of abuse, there is grave cause for concern about the fate of those detained," said Georgette Gagnon, deputy director of Human Rights Watch's Africa division and noted that human rights violations had occurred in the past.
The organization had received unconfirmed reports of torture and at least two executions by suspected rebels, she added, and said: "Sudanese forces and the rebels should comply with the laws of war and spare civilians from harm."
Chad's troubled east, which is also dominated by rebel militias, borders on Darfur. Relations between N'Djamena and Khartoum have been strained for some time.
Both accuse each other of offering rebels asylum and of acting as supply bases.
When Chadian rebels advanced as far as the capital N'Djamena in February, President Idris Deby accused Sudan of supporting them.
