Mexican security forces have arrested 38 members of the Knights Templar drug cartel, as part of an operation to restore order in Michoacan state.
Jesus Vasquez Macias, 37, whom officials described as a leading figure in the gang, was among those detained.
Hundreds of troops were deployed last week after violent scenes as groups of vigilantes clashed with gang members.
The vigilantes accuse the government of not doing enough to protect locals from extortion and violence.
Many members of the so-called self-defence groups are refusing to heed the government’s call to disarm.
Mr Vasquez Macias, also known as “El Toro” (The Bull), was arrested along with two other men and charged with offences related to organised crime, a National Public Security System spokesman said.
The three were detained in the port city of Lazaro Cardenas, Monte Alejandro Rubido Garcia told a news conference.
Federal forces are now in control of 27 of Michoacan state’s 113 municipalities, he said.
“No violent acts have been recorded in these six days and normal life is being gradually restored in the Tierra Caliente area,” Mr Rubido said.
More than 1,200 local police officers are being investigated for possible links to organised crime, he added.
However, vigilante groups say Mr Vazquez Macias is a top hit man, not a cartel leader.
The self-defence groups would applaud the federal government’s work in Michoacan only after the cartel’s top leaders were arrested, spokesman Estanislao Beltran told the Associated Press news agency.
Large areas of the western state have been under the control of the Knights Templar cartel. However, earlier this month, vigilante groups began occupying much of the gang’s key footholds.
The Knights Templar, who claim to protect the local population from attacks from rival gangs, have accused the self-defence groups of siding with the New Generation drug cartel based in neighbouring Jalisco state.
They say the fact that some of the vigilantes are carrying powerful assault weapons shows they are not local farmers but are in the pay of the New Generation gang.
The government of President Enrique Pena Nieto has repeatedly denied that it has lost its grip on Michoacan despite several similar surges in the number of troops and police in the state in the year since he came to office.