Virginia ? The Transportation Security Administration is denying allegations that an airport screener seized a toddler’s sippy cup and mistreated his mother, taking the unusual step of posting security camera footage on its Web site.

The TSA said in a statement that the incident and the videotape demonstrate that its “officers display professionalism and concern for all passengers.”

At issue is whether Monica Emmerson, a former Secret Service officer, was improperly detained June 11 after she spilled water out of her child’s sippy cup at Washington’s Reagan National Airport.

TSA has banned most fluids at airport security checkpoints for nearly a year because of concern about possible liquid explosives.

“I was distraught. I opened my son’s sippy cup. I twisted off the top. I wanted to drink the water. It spilled out,” Emmerson said Saturday.

Emmerson said an officer threatened to arrest her after the water spilled, telling her she was “endangering the public.” She said there was no place to dump the water near the security area, and that she was worried when her son started wandering away from her.