(CNN) -- Former members of a Guatemalan special forces unit are believed to have been involved in the killings of 27 people on a farm in a northern province, the country's president said.
President Alvaro Colom said Tuesday that the former members of the Kaibiles, as the military group is known, had a hand in the massacre that led to a state of siege being declared in the province of Peten.
Authorities have blamed the killings on the Zetas Mexican drug cartel, which has been linked before to the Kaibiles.
On Tuesday, authorities released details about one suspect who has been arrested in connection with the murders.
Hugo Alvaro Gomez Vasquez, also known as "the Witch," has a strong relationship with the Zetas, the state-run AGN news service reported.
He was picked up on a triple murder charge related to the mass killings in Peten, officials said. He is accused of kidnapping and killing three people related to the owner of the farm where the 27 bodies were found. Investigators did not say if he was directly linked to the 27 dead.
Authorities have sent eight teams into the field, consisting of 25 investigators, to try to shed light on the murders.
The killing spree, which officials said took place late Saturday into early Sunday, is one of the nation's worst since the end of the civil war in 1996.
The killers decapitated several victims and left their body parts strewn across the terrain, police said.
Colom called the killings "sadistic and perverse."
Survivors who described the killing spree included a pregnant woman who said she covered her daughters and begged for mercy, Guatemala's Prensa Libre reported. The woman said the group that attacked the farm consisted of more than 50 armed men in fatigues, who had Mexican accents.