■ Gunmen ambushed a police convoy in Mexico, killing eight officers and five prosecution investigators.

Nation’s worst mass-slaying of law enforcement since late 2019

MEXICO CITY — Gunmen apparently from a drug gang ambushed a police convoy Thursday in central Mexico, killing eight state police officers and five prosecution investigators in a hail of gunfire, authorities said.

The massacre of the 13 law enforcement officers in the State of Mexico was the country’s single biggest slaying of law enforcement since October 2019, when cartel gunmen ambushed and killed 14 state police officers in the neighboring state of Michoacan.

The Thursday ambush sparked a huge search for the killers in a rural, gang-plagued area southwest of Mexico City, which is surrounded on three sides by Mexico State. The dead law enforcement officers worked for the state.

While Mexico State contains suburbs of the capital, it also includes lawless mountain and scrub lands like the one where the attack occurred.

Rodrigo Martínez Celis, the head of the state Public Safety Department, said soldiers, marines and National Guard troops were combing the area by land and from the air looking for the killers.

“The convoy was carrying out patrols in the region, precisely to fight the criminal groups that operate in the area,” Martínez Celis said. “This aggression is an attack on the Mexican government.

“We will respond with all force,” he added.

There was no immediate indication as to what gang or cartel the gunmen might have belonged to. Several operate in the area around Coatepec Harinas, where the attack occurred.

Meanwhile, Mexico sent hundreds of immigration agents, police and National Guard officers marching through the streets of the capital of the southern state of Chiapas to launch an operation to crack down on migrant smuggling.

The parade Friday in the city of Tuxtla Gutierrez came one day after Mexico announced it was banning entry for nonessential travel on its southern border with Guatemala to prevent the spread of COVID-19. The restrictions went into effect Friday.

Mexico will deploy checkpoints and drones and station officers along the Suchiate River, which marks part of the border, to deter irregular entry. The crackdown is especially aimed at people traveling with minors.

“The Mexican government will carry out … operations on the southern border to protect the rights and safety of migrant minors from several Central American nations who are used by criminal networks as a passport to reach northern Mexico,” Mexico’s National Immigration Institute said in a statement.

The institute said that since the beginning of the year, 4,180 minors, both accompanied and unaccompanied, had been found in Mexico without proper travel documents. Most came from Central America.

The institute said adults traveling with the minors said “guides” had advised them having children along would make it easier to enter Mexico and the U.S.

Mexico staged similar but smaller shows of force last year to discourage migrant caravans from trying to enter from Central America.