The offices of major Mexican newspaper El Norte came under attack Sunday for the third time this month.
Several masked, armed men broke into a branch office of the prominent newspaper located near the northern city of Monterrey, poured gasoline and ignited it, reported the Associated Press. El Norte's website said none of the 15 people working in the Sierra Madre office were injured, as firefighters from the San Pedro Garza Garcia municipality quickly put out the fire.
According to CNN, the men threatened a security guard in order to enter the building.
After the attack, Reforma Group, which publishes the newspaper, sent out a message to its employees.
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"With great respect and admiration we aim toward a different type of heroic action: one that is done by soldiers of freedom. Those who, with bravery, talent, compromise and discipline, not in a quick instant but in decades of battle, are able to improve the lives of others," the message read. "We are referring to the 3,500 people who work at Grupo Reforma, including editors and advisers. Those who make an effort to make a claim against the unacceptable conditions which have led our compatriots to violence and desperation."
The AP said two other outlying offices of the paper were attacked with grenades and gunfire on July 10.
No group has claimed responsibility for Sunday's fire, according to UPI. But journalists have been targeted by drug cartels since the government declared war on the gangs, resulting in 70 deaths of people working in the media since 2000.