Seven bodyguards have been arrested over their alleged involvement in the murder of a popular Mexican mayor, authorities have said.

Carlos Manzo, the mayor of Uruapan and an outspoken critic of cartel violence, was shot dead on 1 November at a public event marking the Day of the Dead.

The office of the attorney general of Michoacán state stated the public servants had been detained for their probable participation in the crime of aggravated homicide, in commission by omission regarding Manzo's killing.

This follows the arrest on Wednesday of a man police described as the mastermind behind the murder, who officials said had connections to a powerful cartel.

The attorney general's office confirmed that the seven guards were captured by both state and federal officials, including the National Guard.

Authorities led the suspects out of a municipal building located near the scene of Manzo's assassination, according to reports.

The 40-year-old mayor was attending a Day of the Dead ceremony—honoring deceased family and friends—when he was shot seven times, prompting bystanders to flee in panic.

Manzo's assassination ignited widespread protests and raised significant questions regarding the failure of his security detail to intervene during the attack.

The assailant was subsequently restrained and shot by Manzo's bodyguards.

Manzo had been vocal about the extortion and threats faced by avocado growers in the region, as well as urging the Mexican government to take stronger actions against the cartels.

The Jalisco New Generation Cartel (CJNG), which the Mexican security minister has implicated in Manzo's murder, is notorious for drug trafficking and targeting officials who oppose them.

On Wednesday, officials apprehended the alleged mastermind of the assassination, identified only as Jorge Amando.

While the CJNG is regarded as the most influential criminal entity in Michoacán, numerous other gangs also vie for control of drug and smuggling routes, resulting in deadly confrontations.