Fighting raged for several hours after Ovidio Guzmán López was found during a routine patrol in the city of Culiacán.

Eventually, Police withdrew without Mr Guzmán in their custody to avoid further violence, officials said.

Shocking allegations in ‘El Chapo’ trial
Mexico’s security minister, Alfonso Durazo, told Reuters news agency that a patrol of National Guard militarised police came under intense fire from outside the house where they had located Mr Guzmán, forcing them to retreat from the building for their own safety and “to recover calm in the city”.

A lawyer for the Guzmán family told the Associated Press (AP): “Ovidio is alive and free.”

Mexico’s President Andrés Manuel López Obrador said he would hold a meeting of his security cabinet to discuss the incident.

Mr Obrador was elected on a platform of cracking down on Mexico’s drug cartels, and has tasked a new security force, the National Guard, with fighting them.

Under El Chapo’s leadership, the Sinaloa cartel was the biggest supplier of drugs to the US, officials say.

With the kingpin now behind bars, the cartel is said to be partially controlled by Ovidio Guzmán Lopez, who is accused of drug trafficking in the US and believed to be in his twenties. But he is not one of El Chapo’s best-known sons.

What happened in Culiacán?
The state government said Mr Guzmán was found in a house by a police patrol on a routine search.

It said cartel members subsequently launched the huge attack in an attempt to seize him back from the authorities. Fighters also attacked security forces in other parts of Culiacán.

Witnesses described scenes of panic in the city, a stronghold for the Sinaloa cartel, as families with small children fled from gunfire.

Trucks were set alight in the streets to block roads

“No one knows what is going on but everyone is afraid and they have told us to not come in to work tomorrow,” Ricardo González, a city resident, told AP.

The Sinaloa state government told residents to remain calm and stay off the streets

A purported mugshot taken of Mr Guzmán while he was detained by police was shared widely on social media.

Sinaloa state’s head of security, Cristobal Castañeda, told the Televisa network that two people had been killed and 21 injured, according to preliminary information.

Some police officers were wounded, local officials said, but would not provide further details.

The authorities say they are working to restore order in the city

Cars and jeeps have were also set on fire during the clashes

As fighting brought the city to a standstill, the Sinaloa state government said an unknown number of inmates had escaped from the Aguaruto prison.

It said it was “working to restore calm and order” and called on residents to “remain calm, stay off the streets and be very attentive to official advisories on the evolving situation”.

“El Chapo” (or “Shorty”) ran the Sinaloa cartel across northern Mexico.

Over time, it became one of the biggest traffickers of drugs to the US. He escaped a Mexican jail through a tunnel in 2015, but was later arrested. He was extradited to the United States in 2017.

He was accused of having helped export hundreds of tonnes of cocaine into the US and of conspiring to manufacture and distribute heroin, methamphetamine and marijuana.

El Chapo, 62, was found guilty in New York of 10 charges, including drug trafficking and money laundering.   (BBC)