Irish rockers U2 and British singer Ed Sheeran have cancelled scheduled concerts in the US city of St Louis.
It comes amid security concerns after police there said they could not provide protection for the audience.
In a statement, U2 said: "We have been informed by the St Louis Police Department that they are not in a position to provide the standard protection for our audience as would be expected for an event of this size.
"We have also been informed that local crowd security personnel would not be at full capacity.
"In light of this information, we cannot in good conscience risk our fans’ safety by proceeding with tonight’s concert.
"As much as we regret having to cancel, we feel it is the only acceptable course of action in the current environment."
Promoter Live Nation say those who purchased tickets online will receive a refund on the credit card tickets were ordered on.
Refunds for non-internet purchases will be available from Monday at point of purchase.
While British singer Ed Sheeran said: "With the safety of the fans being of upmost concern, and after consulting with local officials, who could not fully commit to providing a sufficient amount of police and other city services support, we felt it was in everyone’s best interest to cancel Sunday night’s show.
"While we regret to have had to come to this decision, we do look forward to returning to St Louis as soon as Ed’s schedule will allow in 2018."
Protests have errupted in the city after the acquittal of a white former police officer in the 2011 fatal shooting of a black man.