Tijuana's top police official, Alejandro Lares Valladares, stepped down from his position on Friday, saying that he "wanted to avoid the continuation of the perverse media campaign" against the department.
Lares did not elaborate on the specific reasons for his resignation. He defended his record, citing a "marked decrease in crime rates in all areas, except — I have to recognize — in homicides, due to armed attacks among small-scale drug vendors and dealers."
There was no immediate comment from Tijuana City Hall. Mayor Jorge Astiazarán was expected to formally accept Lares' resignation at a city council meeting later in the day. Also expected to resign was Bernardo Padilla, who holds the city's No. 2 position of secretary-general.
An attorney with a specialty in criminology, Lares joined the Tijuana police in 2006, serving for several years as the department's international liaison.
The department currently counts close to 2,200 officers. While common crimes have dropped, a marked rise in homicides — 670 in 2015 — has raised alarm about the resurgence of criminal groups in the city.
Lares has been keen on introducing new crime-fighting technologies, including tablets, police cameras and drones. He also created the department's first division of criminal intelligence.
"Lares did a lot in the area of criminal investigation, but unfortunately, the police force is showing symptoms of a lack of internal leadership," said Gustavo Fernández de León, president of the business group Coparmex.
Lares "has built a strong relationship with society, and that is important," Fernández said. "But what we need is someone with a stronger hand internally."
The resignations come at a politically heated time in the city, with much jockeying in anticipation of elections in June, when Tijuana voters are scheduled to choose their next mayor and new state legislators.
Sandra Dibble is a reporter at the San Diego Union-Tribune.