Rocker Lenny Kravitz was among the stars at a New Orleans concert to raise funds for fisherman affected by the Gulf oil spill.
The musician, who lives part-time in the Louisiana city, said he was "concerned" for local people.
Mos Def, John Legend and Annie DiFranco also performed on behalf of the Gulf Relief Foundation.
Since 20 April, oil has been escaping at a rate of 210,000 gallons a day after an explosion on a BP-leased rig.
Poor weather at the event led to an outdoor stage being moved indoors.
Kravitz also said: "I don't know how to stop this oil, that's not my department.
"I get to go speak with these people, I get to understand what they're going through, what it's like for them to be completely shut down and not knowing what's going to happen.
"I'm just here to play some music and just assist these people in having a voice," he added.
Actor Tim Robbins, who was also at the concert, said it is shameful how the disaster is being handled.
Proceeds from the Gulf Aid benefit gig will also go towards the restoration of coastal wetlands devastated by the oil spill.