Method and apparatus for transmitting secure cell broadcast messages in a cellular communication network

A method and apparatus is provided for transmitting a cell broadcast message in a mobile communication network comprising in a message control node receiving a initiation request identifying a first message payload segment to be transmitted, determining an authentication group for which the first message payload segment is intended and determining a first encryption key associated with the determined authentication group. The first message payload segment is encrypted using the first encryption key. A message payload is aggregated comprising the encrypted first message payload segment and at least a second message payload segment. The cell broadcast message comprising the aggregated message payload for message broadcast is transmitted within at least a part of the communication network. A method and apparatus is also provided for decrypting a cell broadcast message at a mobile terminal.