Mexico's Green Party is demanding an investigation into the killing of its candidate for a congressional district in the central state of Puebla.

Juana Irais Maldonado is one of more than a dozen candidates who have been killed ahead of July 1 elections in Mexico.

Maldonado was running to represent the Huauchinango district.

The Green Party urged authorities Saturday to put an end to the violence and aggression faced by candidates for public office.

Local media previously reported that Maldonado and another party member were ambushed after departing a campaign event in a vehicle.