Tijuana Mayor Montserrat Caballero says she does not know who is responsible for the threats but is taking precautions.

In a social media post on Monday, Mayor Montserrat Caballero said that she had received threats following an operation to confiscate 1,700 firearms from a criminal group. Seven dead bodies were also found by police stuffed in a pickup truck earlier this week.

“I have received threats, so I am going to live at the base,” Caballero said. Local media have reported the barracks are on the southern edge of Tijuana, about 8 kilometres (5 miles) from city hall.

Mexican President Andres Manuel Lopez Obrador confirmed the threats during a press conference on Tuesday, blaming “organized crime groups”.

“She’s being protected, since about two weeks ago,” Lopez Obrador explained. “We reached an agreement to help protect her and will continue to do so.”

The Tijuana city council also released a statement, saying that the threats were a result of Caballero’s “strong results in weapons seizures and arrest of violent suspects”.

The decision to move Caballero to a military base underscores the violence and retaliation faced by those who act against or bring attention to the activities of armed groups in Mexico, including drug trafficking. Some of the groups have alleged ties to state authorities, spurring fears they can lash out with relative impunity.

Tijuana, which has more killings than any other city in Mexico, has recorded a nine percent increase in murders over the last 12 months, partly due to skirmishes between rival criminal groups wrestling for control of resources and influence in the border city.

“Today we are saying to the organized crime groups that are committing these crimes, that Tijuana is going to remain open and take care of its citizens,” Caballero said in a video in 2022.

“We also ask them to settle their debts with those who didn’t pay what they owe, not with families and hard-working citizens.”