Brazilian judge Denise Tarin revoked her own injunction today blocking the Rio de Janeiro leg of the Live Earth global series of concerts.

The decision came after Live Earth organizers secured approval from Rio's police department and met security concerns for the South American event.

Organizers where shocked by the Wednesday ruling to stop what would be the only free concert in the Live Earth series. The state prosecutor's office estimated that there were insufficient officers available to police a crowd that could top 700,000.

Rio police are concentrating their security efforts on preparations for the Pan American Games, which begin on July 13.

"In the case of such big events the prosecutor's office always asks for a police assessment and they told us they didn't have enough personnel to provide security at the event," a spokeswoman said.

The municipal RioTur tourism authority, which is involved in the concert's organization, obtained a police guarantee on Thursday that there would be adequate security at the event.

Organizers say dozens of observation towers, platforms and police cameras will be used to provide security at the concert's Copacabana Beach setting.

Last month, Istanbul was dropped from the list of cities set to hold the concerts because of a lack of interest and security concerns.

The court injunction in Rio had triggered fears that a second cancellation would tarnish the seven-continent Live Earth series.

Lenny Kravitz, Macy Gray and Pharrell Williams will headline Rio's Copacabana Beach bash.