On the campaign trail, Sheinbaum had promised to largely continue the security policy of her mentor and predecessor Andres Manuel Lopez Obrador, which prioritized addressing the root social causes of crime rather than attacking the cartels - an approach nicknamed "hugs not bullets" after a catchphrase of the former president.

But initial signs from her first months in office suggest a more aggressive approach with the most substantial deployment in at least six years of military and naval troops, as well as special forces and heavy weaponry to Sinaloa since an intra-cartel war broke out in September.

High-profile arrests and large drug seizures have followed, including a record bust of over a ton of fentanyl.

That more front-footed strategy could align well with President-elect Donald Trump, who has called on Mexico to do more to stop the flow of drugs, and migrants, to the U.S.

But it also risks further inflaming violence and homicides, as a more confrontational position has done in the past in a country where cartels are heavily armed with military-grade weapons.

Sheinbaum's office did not reply to a request for comment.

"There is a change without a doubt ... we are seeing signs that the strategy of hugs and not bullets is on the way out," said Vicente Sanchez, a security expert and member of Mexico's National System of Investigators, a government agency that works to improve the quality of Mexican research.

Security experts said they believe the new strategy is partly a response to Trump's threat to impose 25 percent tariffs on products from Mexico if the country does not curb drug trafficking and the illegal crossing of migrants into the United States.

Some have also taken it as an indirect admission that Lopez Obrador's less confrontational strategy did not work, with many experts saying it helped organized crime groups entrench power in vast swaths of the country.

The U.S. ambassador to Mexico, Ken Salazar, publicly criticized the approach, saying it had "failed" and "Mexico is not safe."

MILITARY TO THE STREETS

Some security experts have drawn comparisons between the operations in Sinaloa and the military war waged on the cartels by then-President Felipe Calderon in 2006. That triggered a spiral of violence to which many analysts trace the continued high homicide rates Mexico.

The United Nations has repeatedly criticized the use of the armed forces in the fight against crime in Mexico, arguing that it encourages human rights violations. The Mexican government denies that security in the country has been militarized or that human rights abuses are common.

Key to Sheinbaum's crime-fighting strategy is her new security chief Omar Garcia Harfuch, an experienced policeman who worked for the president while she was mayor of Mexico City.

Sheinbaum sent Garcia Harfuch to Sinaloa to oversee operations.

"We know how difficult it is to pacify the country," he said last week after an investigator from his ministry was killed in Sinaloa.

The confrontation between rival groups in Sinaloa, which intensified on Sept. 9, has so far killed some 650 people, with more reported missing. In an attempt to contain the conflict, the local security chief was replaced by a military officer over the weekend.

In the same week, at least three soldiers were killed by land mines laid by organized crime in two separate locations in the western state of Michoacan.

For some experts there is a danger if Sheinbaum seeks to replicate her strategy in Sinaloa across the country.

"Each one (criminal group) has its own personality, its own mark, and we have to find the part that hurts them," said Tomas Guevara, an expert on security issues in Sinaloa.