MEXICO CITY (AFP) - A journalist was shot dead on Monday afternoon (Aug 22) in southern Mexico, the authorities said, shortly after posting online about the disappearance eight years ago of 43 students from a nearby area.

Mr Fredid Roman, who published his work on various social media pages and contributed to a local newspaper, was found dead in his car in the city of Chilpancingo, the capital of Guerrero state, the local prosecutor's office said on Monday evening.

The case of the 43 students from Guerrero, who went missing in 2014 after commandeering a bus to head to a protest, is considered one of the worst human rights disasters in Mexican history.

The case was forced back into the spotlight last week when a truth commission branded the atrocity a "state crime" that involved agents of various institutions.

A few hours before his death, Mr Roman published a long Facebook post titled "State Crime Without Charging the Boss", in which he mentioned an alleged meeting between four officials at the time of the students' disappearance, including former attorney-general Jesus Murillo Karam.

Murillo Karam was arrested after the publication of the truth commission report last week, while dozens of warrants were issued for suspects including military personnel, police officers and cartel members.

It was not immediately clear if Mr Roman's recent post on the missing students or his other journalistic work played a role in his death.

Twelve journalists have been killed in Mexico so far this year, according to the government, while the NGO Reporters Without Borders (RSF) lists nine. Some media outlets have put the figure at 15 or 16.

With about 150 journalists murdered since 2000, according to RSF, Mexico is considered one of the most dangerous countries in the world for the press.

Most of those murders remain unpunished.