Thousands of soldiers took control of the northwestern Mexican city of Culiacan on Friday after the capture of Ovidio Guzman, the son of notorious drug lord El Chapo, in an operation that left 29 people dead, AFP reported.

Nearly 4,500 soldiers are patrolling the streets of the city of 800,000 and its suburbs after the Sinaloa cartel launched an offensive to try to prevent the capture of one of its alleged leaders, a 32-year-old.

“The situation has been calm in recent hours,” Mexican President Andres Manuel Lopez Obrador said at his daily press conference.

“Ten soldiers (…) unfortunately died in the line of duty,” Defense Minister Luis Cresencio Sandoval announced, adding that there were also “19 deaths” among the alleged perpetrators.

Another 35 soldiers were shot and wounded and 21 people were arrested during the operation, which authorities said resulted in no casualties.

Among those killed was a senior army officer, Sandoval said, adding that his patrol was attacked after the arrest of Ovidio Guzmán, alias “El Raton” (“The Rat”), accused of leading a faction linked to the Sinaloa cartel, the founder four decades ago of its father.