A Kurdish rebel spokesman claimed Friday that about 2,400 Kurdish civilians trapped in a mountain ravine in Iraq were killed in a poison gas attack Aug. 30 by Iraqi warplanes.

Word of the alleged attack was delayed because it took survivors 10 days to reach southern Turkey and contact rebel officials, said the spokesman for the Kurdistan Democratic Party, whose guerrillas are fighting for automony.The spokesman said the victims were fleeing an Iraqi military offensive by trekking to Turkey.

There was no independent confirmation of the reported gas attack. But the spokesman claimed the casualties raised the number of Kurds killed by Iraqi chemical weapons since early August to around 4,300.