NEW : Shortly before the collapse , police warned the audience of severe weather . The crowd was told to stay in their seats and not move for a few minutes while they waited out the storm. `` We are all right . We are praying for our fans , '' tweets Sugarland . A witness says he saw some people trapped .
NEW : Shortly before the collapse , police warned the audience of severe weather . At least 24 people are injured , and police say the death toll might rise . `` We are all right . We are praying for our fans , '' tweets Sugarland . A witness says he saw some people trapped .