Guerrero gang leader Gildardo Lopez Astudillo, a key figure in the disappearance of 43 Mexican students last year in the town of Iguala, has been arrested.
The Mexican government says Gildardo Lopez Astudillo, known as “El Gil” is a leader of the Guerreros Unidos drug cartel.
It alleges Gildardo Lopez Astudillo, 36, gave the orders to abduct and kill the students.
There have so far been 111 arrests over the 2014 disappearances.
The Mexican attorney-general’s office says its investigations show the Guerreros Unidos gang were handed the students by corrupt police in Iguala.
The office has said because Guerreros Unidos thought the students were members of a rival gang, they murdered them and then disposed of the bodies by burning them at a rubbish dump outside the city.
Official accounts contrast with a report issued by an international group of experts appointed by the Inter-American Human Rights Commission (IAHRC).
Their report earlier this month alleges that the Mexican authority’s investigations were deeply flawed, and included the disappearance of key evidence.
According to the experts, who visited the site where the Mexican authorities say the bodies were burnt, a fire fierce enough to incinerate the 43 students would have lasted over 60 hours and would have required tons of wood or rubber which would have burnt down the surrounding vegetation.
No fire was reported in the area at the time of the disappearance.
Earlier this week Austrian forensic experts announced they had identified the remains of a second victim found at the rubbish dump where the students’ bodies were allegedly burnt.
The relatives of the 43 students have demanded that the government investigates the possible involvement of high-ranking members of the military in the disappearances.
The apparent massacre of poor, rural students has posed problems for President Enrique Pena Nieto who took office in 2012 promising to stamp out drug-related violence.
Enrique Pena Nieto has been criticized for his handling of the case and accused of trying to wrap it up without a comprehensive investigation.
Correspondents say by charging “El Gil” with the disappearance of the students, the President would enable a swift end to the investigation.
International experts have disputed the government’s accounts of what happened and have said its investigation was deeply flawed.
A 6.5 magnitude earthquake shook Mexico on Saturday killing at least two people and knocking out power in the capital.
The quake, which struck the western state of Guerrero at 19:47 local time, was strongly felt in Mexico City.
At least two people have died in the state, but reports suggest the country has escaped major damage.
An 18-year-old man was killed when a roof collapsed in Iguala, a small city between the capital and the tourist resort of Acapulco.
A second man, aged 25 was killed when a rock fell on a small van on the Mexico City-Acapulco highway, according to Reuters news agency.
The epicenter of the quake was 28 miles from Iguala in Guerrero and the tremor was 40 miles (65km) deep, the U.S. Geological Survey reported. The quake, originally reported as 6.7 on the magnitude scale, was also felt in other states including Michoacan, Puebla and Hidalgo, local media reported.
“I was dreadfully afraid, I thought it was never going to end,” Laura Gonzalez, who was in a bar in the capital at the time of the quake which lasted 40 seconds, told Reuters.
A severe earthquake in 1985 killed thousands of people and wrecked parts of Mexico City, and many residents live with the fear of a repeat.
Shoppers at a popular department store in Condesa rushed out to the street, some of them crying and shouting, and traffic lights were out at several intersections, causing traffic jams.
“The most damage was in Iguala because the epicenter was very close to there,” a spokesman for Guerrero emergency services told Reuters.
Landslides had closed highways in the Pacific coast state but the duty fire officer in Acapulco said that while residents of the port city felt the earthquake and telephone services were down, there were no reports of major damage.
Power was knocked out in many districts of the capital and one building was evacuated, but Mexico City Mayor Marcelo Ebrard said water services,
the subway and the airport were working normally.
“The city center is fine, there are people skating on the ice rink,” Mexico City emergency services spokesman Manuel Mondragon said of the winter entertainment facility set up in the central Zocalo square.
“At the moment, there is no reason for concern,” he told Reuters.
A source from phone operator Telcel said services went out briefly in some sections of the city as the mobile network was overloaded with people trying to call family and friends.