Gunmen riding motorcycles stormed a village hall in Mexico’s Oaxaca state and shot dead the mayor of San Mateo Piñas, Lilia Gema García Soto, in a brutal attack that has left the country reeling once again from political violence.

Witnesses said the attackers opened fire on García Soto and a local official, Eli García Ramírez, who was meeting with her at the time. Two municipal police officers were also injured before the gunmen escaped.

The motive behind the killing is still under investigation, but local leaders in small towns across Mexico are frequently targeted by criminal gangs when they are seen as obstacles to their influence.

Authorities say federal agents have been deployed to assist in the manhunt for the four attackers.

García Soto becomes the second mayor to be murdered in Oaxaca this year, following the fatal ambush of Santiago Amoltepec's mayor in May, where two other people were also killed.

The Oaxaca governor condemned the killing and vowed justice, stating the crime would not go unpunished.

The rising violence against local politicians in Mexico has become a national crisis, especially in areas where criminal groups hold strong influence.

Though most killings occur in remote municipalities, the violence has reached major cities, including Mexico City, where two senior aides to the mayor were shot dead last month.