Photos showing the lifeless body of a seven-month-old baby, murdered alongside his parents, have horrified Mexico.

The infant and his young parents were gunned down in the city of Pinotepa Nacional in Oaxaca on Friday night.

Graphic pictures, which STV News has chosen not to publish, show their blood-soaked bodies with the little boy lying face down on his father's torso.

The images have been shared on social media by Mexicans angry at the level of violence in the country.

Many said the young boy represented Mexico's spiralling gang problems in the same way the image of Alan Kurdi, the Syrian boy whose body washed up on a Turkish beach, symbolised the global refugee crisis.

One Facebook account called Solo Acapulco asked:

The post has been shared 52,000 times.

In an opinion column, Octavio Martínez Michel published a Mexican flag with a drawing of the dead child in the background and wrote:

Prosecutors told CNN that the murder of the family appears to be linked to drugs.

A memorial was held for the family on Monday with hundreds of people, including young children, lighting candles and praying.