MEXICO CITY (Reuters) - Mexico suffered its worst year for homicides in 2019, with a record 34,582 victims, official data showed on Monday, underscoring the challenge President Andres Manuel Lopez Obrador faces while waging war on drug cartels.

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Lopez Obrador assumed the presidency in December 2018 pledging to pacify the country with a less confrontational approach to security, but violence has continued rising, with the number of homicide victims 2.5% higher in 2019 than a year earlier, according to the security ministry data.

Separate security ministry figures using an older methodology that refers to the number of homicide investigations showed an increase to 29,401 last year from 29,100 in 2018.

Mexico has used its military in a war on drug cartels since late 2006. But, despite the arrest or killing of leading capos, the campaign has not succeeded in reducing drug violence and has led to more killings as criminal groups fight among themselves.

To tackle the problem, Mexican officials last week presented lawmakers a proposal to overhaul the criminal justice system, paving the way for the Senate to take up the plan next month that could ease security cooperation with the United States.

Concern has grown over the president’s strategy, which he says still needs time, after two major crises in recent months.

Critics blasted the government as weak in October when it ordered security forces to release the captured son of convicted kingpin Joaquin “El Chapo” Guzman under pressure from marauding cartel henchmen in the northern city of Culiacan.

Then, in early November, three mothers and six children were massacred by suspected cartel gunmen in northern Mexico, sparking outrage and revulsion at home and abroad.

According to a draft of the criminal justice reform reviewed by Reuters, the plan would allow private communications to be used as evidence and limit legal challenges to avoid extradition delays for criminal suspects, many of whom are U.S.-bound.

Mexican Attorney General Alejandro Gertz told senators the plan would attack entrenched corruption and impunity as well as the roots of criminal activity.