Authorities deploy 10,000 soldiers nationwide to quell violence following the drug lord’s killing in a military operation.

Mexico remains on high alert after a wave of reprisal attacks triggered by the killing of its most wanted drug cartel leader, even as President Claudia Sheinbaum claimed the country is at peace and life is returning to normal.

Some 10,000 soldiers have been deployed across 20 of Mexico’s 32 states to maintain order following the killing of Nemesio “El Mencho” Oseguera in a military operation about 130km (80 miles) from Guadalajara city on Sunday.

Guadalajara is the capital of western Mexico’s Jalisco state – the stronghold of Oseguera’s Jalisco New Generation Cartel (CJNG) – where at least 2,000 soldiers have been sent.

Schools in Guadalajara and several other Mexican cities were closed on Monday. However, public transport partially resumed, though buses carried few passengers, as people witnessed a slow return to normalcy.

Security Minister Omar Garcia Harfuch said on Monday that at least 74 people were killed, including 25 National Guard officers, in the operation that killed the cartel boss and the subsequent violence over the killing of the 59-year-old drug kingpin, one of the most wanted men in Mexico and the United States.

“El Mencho” was considered the last of the drug lords who acted in the brutal mould of the now-imprisoned Joaquin “El Chapo” Guzman and Ismael “El Mayo” Zambada, of the rival Sinaloa Cartel. He was a founding member of CJNG, which was formed in 2009 and has grown into one of Mexico’s most violent crime organisations.

Following his killing, suspected CJNG members set fire to cars in several states and blocked numerous roads. They also attacked banks, petrol stations and shops.

Al Jazeera’s John Holman, reporting from Mexico City, said there was an eerie quiet in the country following El Mencho’s killing.

“Many businesses are closed, and the trucks that the CJNG cartel dragged across roads to stop Mexican security forces and create chaos have been moved out of the way,” Holman said.

Meanwhile, President Sheinbaum said on Monday that peace had returned to the country. “Mexico is calm. We woke up without any roadblocks, and all activity has been restored,” she said.

The White House confirmed that the US provided intelligence support to the operation to capture the cartel leader and applauded Mexico’s army for taking down a man who was one of the most wanted criminals in both countries.

Sheinbaum stressed that only Mexican forces were involved in the operation.

“There was no participation in the operation by US forces. What we have is a lot of exchange of information provided by the US government, but the entire operation, from its planning stage, is the responsibility of [Mexico’s] federal forces,” the president said.

Experts now warn that the “absence of a direct succession” within CJNG could lead to a power vacuum and violent fights to fill it.