The leader of the shock rock group, Billy Tourtelot, had promised fans that a terminally ill man would kill himself in St Petersburg, Florida, during the concert which was to have been broadcast on its website (www.hellonearth.net).
But neither the concert nor the suicide took place. A note on a link to the site said both events had been postponed for a week.
Tourtelot had planned to hold the concert and suicide at a local theatre, but the theatre manager cancelled the performance, fearful of being held liable. Tourtelot then said the concert and suicide would be shown on the internet from separate undisclosed locations in St Petersburg.
On Monday, the city council passed a law banning public suicides and a judge issued an injunction against the suicide at the concert.
Florida Governor, Jeb Bush, also denounced the band's plans and said band members might be prosecuted under a state law banning assisted suicide.
Tourtelot said he wanted to show his support for physician-assisted suicides. He said the terminally ill man was a friend, but did not give any other details about him.