Television pictures showed survivors signalling to rescue helicopters in the provinces of Hadramout and Mahra which suffered 30 hours of heavy rain.
"About 7,000 people have been made homeless and there are about 100 dead or missing. We are still trying to gather more exact figures but communications with some of the affected areas have been cut off," the Yemeni official told Reuters.
President Ali Abdullah Saleh called on Sunday for parliament to approve 20 billion rials ($100 million) in emergency funding for rescue operations and to help rebuild areas affected by the most serious flooding in decades.
Yemeni authorities have declared the provinces a disaster area and Saleh has toured some of the worst affected regions.
Yemen is one of the poorest countries in the world and its government is grappling with a rebellion in the north, unrest in the south and a resurgence of al Qaeda, while a growing number of Somali refugees stretch its resources to the limit.
Situated at the southern tip of the Arabian Peninsula, Yemen is prone to flooding during the monsoon season.
(Reporting by Mohammed Sudam; Writing by Firouz Sedarat; editing by Andrew Dobbie)
- Reuters - Thomson Reuters Foundation
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