Federal District police found two human heads Monday near a military base in Miguel Hidalgo, a borough in the western section of Mexico City, District Attorney Miguel Angel Mancera said.

The human remains were found at an intersection near the border with Mexico state, which surrounds the Federal District and forms part of the Mexico City metropolitan area, along "with a message," Mancera said.

Investigators suspect that the La Mano con Ojos gang, which operates in the Mexico City metro area, committed the killings, Mancera said.

One of the heads was left on an SUV and the other on the ground next to the vehicle, and officials did not say whether the unidentified victims' bodies had been found.

Crime scene investigators gathered evidence at the site.

La Mano con Ojos controls drug dealing in Huixquilucan, located in the Mexico City metropolitan area, officials said.

The gang, known for beheading its enemies, has been fighting for control of the illegal drug trade in the cities of Naucalpan, Atizapan, Tultitlan, Cuautitlan Izcalli and a section of the capital.

Oscar Osvaldo Garcia Montoya, the gang's suspected leader, was arrested in August.

Garcia Montoya confessed to participating in 300 murders and ordering 600 other hits.

The gang leader told investigators he worked for Beltran Leyva cartel boss Arturo Beltran Leyva until his death in December 2009, later going to work for Edgar Valdez Villarreal and Gerardo Alvarez Vazquez.

Valdez Villarreal, known as "La Barbie," and Alvarez Vazquez have both been arrested.

About two dozen men and women have been killed by the gang in Mexico state since November 2010, officials said.