Mexican President Enrique Pena Nieto said Wednesday there was no place for vigilantes in the battle against drug violence, insisting the kind of development seen in Japan was the answer.
Pena Nieto, who took office in December, inherited a drug war that had killed some 70,000 people in six years under his predecessor Felipe Calderon.
Fed up with the police's failure to curb crime, armed groups have spread to at least four Mexican states, manning checkpoints, patrolling streets and in one case killing a "suspect" in a shootout.
The president, who is on an official visit to Japan, said the authorities will deal with the violence, including any from vigilante groups, using the force of the law.
"Mexico has worked towards economic development, which is what people need," he told reporters in Tokyo.
"The prosperity that the country wants will come from that" economic growth.
Pena Nieto has vowed to shift the focus of his country's drug war towards reducing the daily incidences of violence that plague much of Mexico.
He wants to form a paramilitary "gendarmerie" to replace the thousands of troops deployed by his predecessor since 2006. Critics say those troops have been partly to blame for the uptick in violence.
But the government has said soldiers will remain deployed until the level of violence falls.
Pena Nieto, who met with Japan's Prime Minister Shinzo Abe on Monday, said Mexico looked to Tokyo as template.
"I believe Japan is a role model that offers much for Mexico to learn," he said.
"Japan is a model country for Mexico's economic development and technological innovation."