“I wanted to be there to try and comfort, and offer a sign of hope,” Martellot old the Guardian. “I can’t bring people back but I can inspire them with music and when people are inspired they can do anything. That’s why I played ‘Imagine.’”
Martello said he couldn’t perform any other songs after "Imagine." “Even if I wanted to it was just too emotional,” he said, noting that there was blood on his piano from the previous night’s shootings.
Martello also performs under the name Klavierkunst. He's become known for lending his talent and support to other heinous situations, including Charlie Hebdo attacks earlier this year, the Guardian reports.