The head of FEMA's Urban Search and Rescue branch, Ken Pagurek, has resigned due to frustration over the agency's response to the flooding in Central Texas, sources say.

Ken Pagurek, the Federal Emergency Management Agency's Urban Search and Rescue chief, has resigned amid criticism over the agency's delayed response to Texas flooding and efforts by the federal government to dismantle the organization.

More than 1,000 first responders from across the country are helping with search efforts to bring loved ones home to their families.