- A Halloween party where a Department of Homeland Security worker won praise for a costume of darkened skin and prison garb may stall Senate confirmation of the party's host for a second time.

Julie Myers, head of Immigration and Customs Enforcement, called the man's costume "offensive."

Missouri Democratic Sen. Claire McCaskill said Wednesday that she has placed a temporary "hold" on Julie Myers' nomination for the job of assistant homeland security secretary for immigration and customs enforcement until Myers answers questions about the party, including why photographs of her with the costumed employee were destroyed after questions were raised.

"As the leader of that organization, she should have immediately recognized the problem and asked that person to leave," said McCaskill, who has raised previous concerns about Myers' nomination. "And what really happened was, she judged the costume as one that should get a prize and be recognized and she had her photograph taken with the person in the costume -- and only later came back and apologized and said it was a problem."

President Bush used a 2006 recess appointment to put Myers in office after Senate concerns about her inexperience stalled her confirmation. He nominated her again for the job in January.

Myers, 38, was part of a three-judge panel that originally praised the costume -- which featured dreadlocks, black-and-white prison garb and a skin "bronzer" -- for its originality.

She later apologized for what she said were a few "inappropriate and offensive" costumes after other employees complained. The employee who wore the costume has been placed on paid administrative leave pending an inquiry.

ICE spokeswoman Kelly Nantel told CNN Wednesday the photos were deleted because the costume was offensive and because officials feared the images would end up being used on ICE publications and Web sites.