Viral images of the flyer were filmed in portable toilets of a migrant camp in Mexico, and they energized members of Congress. But NPR's reporting suggests the flyer is not what it purports to be.
Three officials from Mexico's immigration agency, two private security guards and the migrant accused of starting the fire, which killed at least 39, face charges of homicide and causing injury.
The two politicians have carried on a furious exchange all week over who is responsible for the surge in migrants at the U.S.-Mexico border. Their debate on Twitter has been less than diplomatic.
U.S. prosecutors say President Juan Orlando Hernández enabled drug trafficking into the U.S., and Democratic lawmakers want punishment. It comes as President Biden seeks Central American aid.