Unidentified gunmen opened fire at around 1am local time on Wednesday at the editorial offices of the Coahuila-based daily Siglo de Torreón, according to the newspaper.

There were no reports of any injuries.

Witnesses describe two assailants on motorcycles opening fire on the building’s façade, according to local news reports.

The assault shattered the building’s glass exterior, and damaged walls, desks and furniture inside.

Bullet casings from AK-47 and AR-15 assault rifles were found at the scene.

The Coahuila State government has condemned the attack, and the State Prosecutor has launched an investigation into the events.

“The authorities must break the cycle of impunity that allows those who wish to silence the media to do so in the most brutal manner,” said IPI Director David Dadge.

Sources at the newspaper told IPI that they had not yet identified a possible motive behind the attack, and had received no warning prior to, or messages after, the incident.

This was the first time that the Siglo de Torreón has suffered such an attack.

Mexico is the Western Hemisphere’s deadliest country for reporters, with at least four journalists murdered so far in 2009 for reasons believed to be related to their work, according to IPI’s Death Watch count.