The Rock ‘N’ Roll Allstars, an 11-piece supergroup comprised of Gene Simmons of Kiss, three former members of Guns N' Roses, Sebastian Bach and many other big names in rock history, were forced to cancel their performance in Sao Luis, Brazil tonight (April 21) due to security issues, according to a message posted on the band's Facebook page this morning.

Rock N' Roll Allstars are saddened to annouce the cancellation of our performance at Metal Open Air Festival in Sao Luis, Brazil.

We regret not being able to attend. We are in South America and are ready to rock, but the circumstances are beyond our control: We were informed before flying to Brazil today that many other artists have pulled out of the event, as well as local security. We are very concerned for the safety of the fans and artists whom are already at the festival.

We are receiving confirmed reports from other bands and friends on the ground that the event is dangerous and a disaster. Please be safe, and we look forward to rocking for you in the future.

Rock on,

Rock N' Roll Allstars

These must be serious if Gene Simmons is cancelling a show. Further research has discovered this account at Antiquiet of the problems currently going on with the Metal Open Air Festival.

The Rock N' Roll All-Stars opened up their 10-date (well, nine dates, as of now) tour of South and Central America on April 19 at the Jockey Club in Asuncion, Paraguay. The show featured 22 songs from its members' catalogs and a few choice covers, such as Led Zeppelin's 'Whole Lotta Love' and Queen's 'Tie Your Mother Down.' The full setlist can be found at Def Leppard's website.

Watch Sebastian Bach Sing 'Welcome to the Jungle' With the Rock ‘N’ Roll Allstars

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