A Czech appeals court has ordered a group of artists who staged a fake nuclear explosion on national TV to be tried again on charges of spreading false information, an official in Hradec Kralove, east of the capital Prague, said Monday.

The artists hacked into a national television weather broadcast and inserted a bright light, followed by a mushroom cloud, which appeared to be rising over the Czech mountains.

Members of the Prague-based Ztohoven art group were acquitted of charges in connection with the hoax in March.

They admitted tampering with equipment at the public broadcaster, Czech Television, but said they were showing how easily TV could be manipulated.

"Is everything we see daily on our TV screens real? Is everything presented to us by the media, newspapers, television, internet actually real?" the group asked on its website.

State prosecutors appealed the verdict acquitting the seven artists and a court has ordered a new trial date to be set.

Czech Television called the stunt "improper" and said it could have scared many people.

In December, the Ztohoven group became the first winners of the new NG 333 prize for young artists from the Prague National Gallery for the project.

A third party nominated them for the award and members attended the awards ceremony incognito.