A man died Saturday after plunging to the floor of the atrium of the National Museum of the American Indian, according to authorities and witnesses.

Leonda Levchuk, a spokeswoman for the museum, said the man apparently jumped.

The National Museum of the American Indian in Washington, D.C. (Bill O'Leary/The Washington Post)

A museum visitor said she saw him on the third level near its four-foot wall about 4:10 p.m. just before the plunge.

The visitor estimated that about 50 other people were there at the time. They were evacuated, she said. The museum is on the Mall.