Mexico City ? Mexican soldiers have captured a suspected drug cartel boss in the most significant arrest since President Felipe Calderon sent thousands of troops to restore order in a western state terrorized by drug gangs, the military said Sunday.

Elias Valencia, a suspected head of the Valencia cartel, was arrested along with four other people Friday at a mountain ranch near the town of Aguililla in Michoacan state, said Gen. Cornelio Casio, one of the officials in charge of the offensive.

Last week, Calderon ordered more than 6,000 soldiers, marines and federal police to his native state of Michoacan, which has seen a wave of drug-related killings and beheadings.

Mexican investigators say Elias Valencia is one of several figures who have run the cartel since his father, Armando Valencia, was arrested in 2003. He and the others were arrested with several hundred pounds of marijuana and an arsenal of firearms, Casio said.