A Mexican journalist was shot dead in front of his wife and two adult children outside his home in a crime-ridden eastern state where 18 other reporters have been murdered since 2010.

Pedro Tamayo Rosas, a 45-year-old who covered the police beat for two online dailies in Veracruz state, was killed late Wednesday in the town of Tierra Blanca, prosecutors said.

The preliminary investigation indicates "there were two assailants who approached Tamayo to greet him at a business in his home," the Veracruz prosecutor's office said in a statement.

A family member said on condition of anonymity that Tamayo had come out to help his wife and two sons man a food stand when he was killed.

The gunmen opened fire and fled in a vehicle, the statement said. Tamayo succumbed to his wounds in a hospital.

The authorities are "not ruling out any line of investigation, including his journalistic work," as a motive, the statement said.

Tamayo worked for the media outlets El Pinero de la Cuenca and Al Calor Politico. 

Mexico is among the most dangerous countries in the world for journalists, with more than 90 media workers killed and 17 others having disappeared since 2000, according to the international press rights group Reporters Without Borders.

In Veracruz alone, 19 journalists have now been murdered in the past six years.