美国国土安全部长将赴龙卷风灾区视察

U.S. Secretary of Homeland Security Janet Napolitano travels to Oklahoma on Wednesday to assess recovery efforts in the city of Moore, where a devastating tornado killed at least 24 people and injured 240 others.

Napolitano's department includes the Federal Emergency Management Agency, which has teams helping with search and recovery operations, damage assessments and providing federal aid to people affected by Monday's tornado.

The storm destroyed large parts of the central U.S. city with what weather officials say were winds of at least 322 kilometers per hour.

The town's fire chief says emergency workers will not stop searching for survivors and plan to go through the rubble of each building at least three times. 

President Barack Obama has declared a major disaster in Oklahoma.  He says the people of Moore are not standing alone, as they recover and rebuild.