Monica Hernandez, from broadcaster WWL-TV in New Orleans, reports that police say 17 people were wounding in the New Orleans shooting.
Police now saying 17 people were wounded in the mother's day shooting in the 7th ward.
More top news
The band announced at a free concert on Friday that they would take over the event's Pyramid stage on Saturday June 25.
The victims were collecting permits and escorts a day after their home town was liberated from the extremists.
Scotland Yard said the male youths will appear in custody at Westminster Magistrates' Court on Saturday.