Twenty-two people were killed and at least 59 injured after an explosion at the end of Ariana Grande's show in Manchester, England, on Monday night (May 22).

Almost immediately, artists began to send prayers to Manchester. While details are still scarce, Greater Manchester police tweeted that they're treating the explosion as a terrorist incident until further notice. NBC News reports that the incident was conducted by a suicide bomber.

Multiple witnesses tell local news outlets they heard an explosion at the end of Grande's show (around 10:30PM local time) and immediately fans began running in panic. Grande's team says the singer was unharmed. The number of casualties is not final. The explosion is said to have happened outside the venue.

"Just hearing about the explosions at the Arianna (sic) concert," Blake Shelton tweeted. "Praying for everybody!! Sick.."

Maren Morris came with a stronger statement:

Eli Young Band, Rascal Flatts, LeAnn Rimes and Chris Young also took to Twitter to express sadness, outrage, disappointment and concern. It wasn't even a year ago that tragedy struck another pop singer's show. Christine Grimmie was killed last June when she was shot by a man at her merchandise table. Country stars reacted similarly then.

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