An international media watchdog group says a Mexican mayoral candidate and dozens of his supporters have beaten up a radio reporter in retaliation for broadcasting an unfavorable report about the politician.

Reporters Without Borders said in a statement Thursday that Ricardo Bravo, the candidate of the opposition Democratic Revolution Party (PRD), and his supporters, burst into the studios of radio La Divertida and attacked Jorge Zamacona Ramirez as he presented a live program.  The group says Mr. Zamacona was seriously injured. 

According to the media watchdog group, Mr. Zamacona said the attack was reprisal for his having broadcast details of documents that related to alleged fraud committed by members of Mr. Bravo's family.

The group has demanded a serious investigation into the case.

Some information for this report provided by AP.