Eight journalists were killed in Mexico in the first half of this year, according to a report by the freedom of expression group Article 19. This surpasses the seven killed in all of 2015. It also means 2016 is already the deadliest year since 10 media workers were killed in 2010.

The report, released on Thursday, also highlighted the doubling of non-fatal aggressions against journalists.

Three of the eight fatal victims were covering police and violence for outlets based in the state of Veracruz. This confirmed Veracruz as the most dangerous state for journalists in Mexico with 17 killed there since 2010.

The report also classified two of this year's murders as "extrajudicial executions" carried out by state employees.

One of these was Salvador Olmos García, a radio host in the tiny indigenous community of Huajuapan de León in the southern state of Oaxaca, who was killed by the local municipal police. Article 19 cast doubts on the police version that a patrol car ran over the journalist in a patch of wasteland by accident. The police said they were chasing him after he escaped from custody when officers took his handcuffs off. He had been arrested for allegedly graffiting a monument.

'Impunity related to attacks on freedom of speech has turned the country into one of the most lethal places for the media in the world'

As well as the frightening increase in the number of deaths, the report also notes a hike in what it calls "aggressions against the press." These range from threats to temporary kidnappings, and arbitrary detentions to intimidation.

The group said that it documented 218 such events between January and June this year, a 115 percent increase on the number registered during the same period in 2015. It said that only a small minority of these came from organized crime and blamed most of the aggression on the state.

"An increase of this magnitude in attacks on the press can only be explained by the lack of a policy of protection and access to effective justice," Ana Ruelas, of Article 19, said in a statement. "The impunity that penetrates Mexico, particularly the impunity related to attacks on freedom of speech, has turned the country into one of the most lethal places for the media in the world."