Around 12,500 Sudanese refugees fleeing inter-ethnic violence in the troubled Darfur region have crossed into Chad over the last four weeks, the UN refugee agency said Saturday.
"For around a month (the border town of) Tissi has registered a huge influx of Sudanese refugees from the Darfur region" said Aminata Gueye, the representative for the United Nations High Commissioner for Refugees (UNHCR) in Chad.
A joint UN-government mission sent to Tissi had registered some 12,500 people, which UNHCR was unprepared for, Gueye said.
"We were not expecting this. It is an urgent situation that worries us," she said.
Refugees arriving in Chad said they were escaping violence between different ethnicities competing for control of Darfur's gold mines.
At least 300,000 people have been killed in Darfur since non-Arab rebels first rose up against Sudan's Arab-dominated regime in 2003, the UN says.
Though the violence has lessened, fighting between soldiers and rebels, as well as tribal violence, is still an everyday occurrence.