A La Familia Michoacana cartel boss in the southern part of the Mexican state of Morelos was arrested by the Federal Police, the Public Safety Secretariat said.
Omar Iram Guzman Ortiz was captured in the city of Tlaltizapan on Saturday, the secretariat said.
Guzman Ortiz was in charge of staging kidnappings and murdering members of rival gangs, the secretariat said.
The 29-year-old suspect was allegedly involved in the killings last Wednesday of seven people, whose headless bodies were dumped in the cities of Jojutla and Puente de Ixtla.
Edgar Adiel Arenas Ortega, 24, Clemente Valencia Gonzalez, 59, Jesus Valencia Rincon, 26, and Obed Gomez Ramos, 28, were arrested along with Guzman Ortiz.
The suspects were also allegedly involved in the beheadings of three people on Thursday and the kidnapping of a couple, the secretariat said.
The Federal Police seized several vehicles, firearms and drugs from the suspects, the secretariat said.
Morelos has been the scene in recent years of turf wars involving rival drug cartels.
The Familia Michoacana, Los Zetas, Pacifico Sur, Sinaloa and Gulf cartels all operate in the state, officials say.
La Familia Michoacana, which was formed in 2006, has been seriously weakened by the arrests and killings of several of its top leaders, and the creation of Los Caballeros Templarios.
The cartel began unraveling after top boss Nazario Moreno's death in a shootout with the Federal Police in December 2010, officials and analysts say.
The La Familia faction led by Jesus Mendez, who was arrested in June 2011, has been fighting the group led by Servando Gomez and Enrique Plancarte, who formed Los Caballeros Templarios in March 2011.
La Familia Michoacana's primary business is smuggling synthetic drugs into the United States, but it is also involved in kidnappings and extortion rackets. EFE