(UPI) -- Medical staff in the Democratic Republic of Congo say they are caught between rebel forces and a government that is blocking crucial supplies.The humanitarian crisis in the eastern Kivu region is worsening as rebel leader Laurent Nkunda refuses to follow President Joseph Kabila's orders to disarm, the BBC reported Saturday. Nkunda dismissed claims by Kabila's office that as many as 1,000 rebels surrendered after heavy fighting with government troops, the BBC reported. Medical staff in Kichanga, the rebels' stronghold, said the government is blocking supplies to help them treat starving children and wounded rebels. Upward of 370,000 people have been displaced by the fighting in the Kivu region since the start of the year.