Mexico Arrests 'Material Author' of Attack Against Missing Students, But Offers No Details

Mexico has captured the alleged "material author" of the forced disappearances of the 43 students from Ayotzinapa, Gildardo Lopez Astudillo, officials said.

Lopez Astudillo, also known as "El Cabo Gil," was arrested on Wednesday while carrying a fake ID and ammunition, said Mexico's national security commissioner.

The arrest comes nearly one year since the September 26 and 27, 2014 attacks against the students in the city of Iguala, Guerrero. Lopez Astudillo was arrested in the colonial city of Taxco, an important tourist destination in the same state, and was called second-in-command of the Guerreros Unidos drug cartel.

Separately, a group of Argentine investigators looking into the case parallel with the government released a statement late Thursday.

The Argentine Forensics Anthropology Team said the Austrian forensics experts cited by the government were reliable, but the group also said — as it did with the first student identified from remains — that it could not confirm the bone fragments that were studied came from a river near a dump where the 43 were allegedly incinerated.

That distinction essentially casts doubt on the government's claim that the Guerreros Unidos carried out the incineration of the students, and raises the specter of possible involvement from some other force or agency.

Parents of the missing have demanded Mexico investigate a military unit in connection to the case, but the government has declined.

Renato Sales Heredia — the country's most recent national security commissioner since the sacking of the previous official in the aftermath of the prison escape of Joaquin "El Chapo" Guzman — read a brief statement and took no questions Thursday after announcing the arrest of Lopez.

There was no word on what intelligence led to the suspect's detention, or what it could mean for the ongoing investigation into the disappearances. Sales also did not say what led him to declare the suspect the "author" of the attacks.

The announcement coincides with a string of government moves in relation to the case in recent weeks, in a sign of intensifying international pressure to solve the case conclusively before the public since a scathing report debunked the government's main line of investigation.

A day earlier, current attorney general Arely Gomez said investigators had identified a second young man among the missing, Jhosivani Guerrero de la Cruz, from remains found in a trash bag dumped in the San Juan river. Only one other student, Alexander Mora, has been positively identified among scattered bone fragments gathered in the area.

Related: Could Mexican Officials Eventually Face Charges for Failings in Missing Students Case?

Felipe de la Cruz, spokesman for the students' parents, told VICE News in a phone interview that the Lopez Astudillo detention is "one more dirty trick of this lying government to make us believe our sons were murdered."

"We think it's weird and by chance how, after the experts' report, they thought it easy to detain 'El Cabo Gil,' when they knew about his existence since the beginning," de la Cruz said. "He has placed several narcomantas [cartel messages] in Guerrero."

The spokesman also said the parents do not trust that "the detainee is in fact El Cabo Gil, and not like the others who were tortured to say what they said about the Cocula garbage dump, since no one knows El Cabo Gil in person."

"We can't trust the attorney general's office," de la Cruz said.

Last November, former Attorney General Jesus Murillo Karam said that Lopez — then still at large — sent a text message to Sidronio Casarrubias Salgado, leader of the Guerreros Unidos cartel, to inform him about the confrontations that were taking place in Iguala.

In that message, Lopez said that the events were an attack from an "enemy criminal group," Los Rojos, another drug-trafficking organization that also operates in Guerrero, the attorney general said. Casarrubias has been detained since October 2014.

On September 6, a panel of experts from the Inter-American Commission on Human Rights refuted Murillo Karam's "historical truth" on the events, which stated the 43 students had been murdered and burned at the Cocula garbage dump, after being attacked and kidnapped in Iguala.

The panel's report scientifically proves that at least 60 hours and huge quantities of fuel would be needed in order to burn all the bodies of the Ayotzinapa students, while the government still maintains the whole process took about 12 hours.

After the report's release, the attorney general's office said it would take the experts' recommendations into consideration, but did not clarify if the new report meant the previous "historical truth" was indeed false.

Mexican President Enrique Peña Nieto is scheduled to meet with parents of the missing 43, along the experts from Inter-American Commission on Human Rights who wrote the recent report. The meeting is set to take place on September 24, two days before the Ayotzinapa attacks anniversary.

The last time Peña Nieto met with the parents was last October, at the presidential residence Los Pinos.

In their statement late Thursday, the Argentine group also criticized the government for not giving the parents of the missing enough time to absorb new information as the case continues to unfold.

Related: 'He's Not Dead,' Says a Father After Mexico Identifies a Second Missing Student

Follow Melissa del Pozo on Twitter: @melissadps