MEXICO (AFP) - The Mexican drug cartel known as Los Rojos is suspected of being behind the murder of a mayor who was gunned down a day after taking office, authorities said Monday (Jan 4).

The killing of Gisela Mota, 33, has shocked the nation, putting a spotlight on the violence plaguing the central state of Morelos and the dangers mayors have faced across Mexico.

The left-of-center former member of Congress was gunned down in her house on Saturday, barely 24 hours after taking her oath of office in Temixco, about 90 kilometres south of Mexico City.

Nearly 100 mayors and more than 1,000 municipal workers have been attacked in Mexico in the past decade, mainly by organised crime groups, according to the Association of Local Authorities of Mexico.

"The lines of investigation indicate that the criminal group Los Rojos was responsible for the murder of Gisela Mota," Governor Graco Ramirez wrote on Twitter.

Morelos State Security Commissioner Alberto Capella told Radio Formula that Mota's murder could be linked to the killing of a person whose dismembered body was found on a highway on December 31 and three other cases.

Two suspects were killed and three others, including a minor, were detained just minutes after Mota's killing.

"There are more people whom we need to detain and we have taken big steps toward clearing up this case," Capella said.

Los Rojos (The Reds) and their archrivals, the Guerreros Unidos (United Warriors), have sought to "generate terror through kidnapping or control of certain areas" in Morelos, the security chief said.

The Guerreros Unidos became notorious last year as the prime suspects in the presumed killing of 43 students who disappeared in the neighboring state of Guerrero.

The governor suggested on Sunday that Mota's murder was linked to his government's decision to put state and municipal police under a "unified command" that has been opposed by some towns.

Ramirez said her murder was "a message and a clear threat for the mayors who recently took office to not accept the police coordination scheme that we have supported and that is being built at a national level."

Ramirez, who like Mota is a member of the leftist Democratic Revolution Party, said she had voiced her support for the police scheme in her city of more than 100,000. She had vowed to clean up crime.

He ordered state police to place 15 municipalities, including Temixco and the neighboring state capital, Cuernavaca, under the unified command following Mota's murder.

Ramirez has clashed with the new mayor of Cuernavaca, former football star Cuauhtemoc Blanco, over the police scheme and their conflict reemerged on Monday.

Ramirez wrote on Twitter that when he met with Blanco over the issue, the sports legend was "rude" to him.

"There are people behind Cuauhtemoc Blanco who want to take advantage of his inexperience so that criminal groups can settle in #Cuernavaca," he wrote.

Blanco strongly denied that people close to him were connected to gangs and he reiterated his rejection of the unified command, which he says has failed to curb crime.

The 42-year-old mayor warned Ramirez that he would be responsible for any attack against him.

"If something happens to me, to the people behind me and to my family, it's on you," Blanco told a news conference.