(CNN) The Federal Emergency Management Agency was so overwhelmed with other storms by the time Hurricane Maria hit Puerto Rico last year that more than half of the workers it was deploying to disasters were known to be unqualified for the jobs they were doing in the field.

That's one revelation from a Tuesday report from the US Government Accountability Office (GAO), which portrays a federal government stretched thin by successive disasters to hit the United States and its territories last year. Hurricane Maria in Puerto Rico followed Harvey and Irma -- all within 26 days of each other, according to the lead author of the report.

"By the time Maria hit Puerto Rico, they were down to the bottom of the barrel," Chris Currie, director of emergency management issues at the GAO told reporters in a conference call Tuesday. "They were having a struggle getting people there -- and not just people, but qualified people."

"The effect of this," Currie added, "is that during the response phase -- and especially during recovery -- these are the folks that are working with the territory and the state governments -- and they're not fully trained on FEMA's programs.

"A lot of the highly trained folks were deployed, not surprisingly, to Harvey and Texas," at least initially, he said.

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