MEXICO CITY — Unidentified gunmen shot to death a lawyer and activist who defended a rural tract against development near the Mexican city of Cuernavaca, Mexico's National Human Rights Commission said Tuesday.

The governmental commission issued a statement condemning the killing of Isaac Medardo Herrera on Monday night.

His neighborhood activist group in Jiutepec, Morelos posted a statement saying the killers knocked on the door of Herrera's home and shot him, before fleeing.

Herrera had led a fight over at least four years to stop plans to build a housing development on the Los Venados tract, an environmentally sensitive woodland area in Jiutepec, just south of Cuernavaca. The development was halted and the area was supposed to be used as a nature reserve.

The commission said at least one other activist has been killed in Mexico so far in 2020.

The Mexican Center for Environmental Rights reported that 15 land defenders were killed in Mexico in 2019. Morelos, the state where Jiutepec is located, was the third most dangerous for environmental activists in 2019.

The state's semi-tropical climate and abundant water, added to its close proximity to Mexico City, have made it the subject of heavy pressure from developers eager to build homes and vacation properties there.