Two concertgoers were taken to Barnes-Jewish Hospital. Spokeswoman Kathy Holleman would not release their names but said the injuries were minor.

Soon after the concert, Knowles, 25, showed up, said Darryl Williams, the hospital's head nurse.

"She was just very concerned about the people injured in the audience," Williams said. "It was unannounced and we kept it very low-key so that she could spend time with them."

Knowles met with the fans for about 45 minutes. "I just thought it was a great thing for someone of her stature to do," Williams said.

A spokesman for Music World entertainment, which represents Knowles, declined comment.

Knowles' world tour opened in April in Tokyo and runs through early September. Other stops include New Orleans, Dallas, New York City, Washington, Boston, Chicago, Denver, Las Vegas and Los Angeles.

She won a Grammy Award in February for contemporary R&B album for "B'Day," her second solo album. She also starred in the movie "Dreamgirls." Pravda.ru