Identifying another 18 suspects in connection with an arson attack on a casino in Monterrey, the authorities in Mexico are offering $1.3m for information leading to their arrests.

Several suspects - including a police officer - have been arrested in connection with the August 25 blaze at the Casino Royale, which caused the deaths of 52 people. Now, the investigation has prompted federal prosecutor Jose Salinas to call on the public for help in the search for these latest suspects.

It is believed that those that carried out the attack were working for the notorious Zetas drug cartel and that the casino owner, Raul Rocha Cantu, received extortion threats but had refused to pay. According to reports, he has now fled to the US.

Sketches of six of the suspects have now been released to the public.