In recent months, gangs have shot at police with M-16 and AK-47 assault rifles in multiple lethal attacks, raising questions about the source of their weaponry. Now, an investigation has unearthed evidence that the military itself is trafficking guns, and El Salvador's attorney general has named Defense Minister David Munguia Payes, the nation's top military official, as being involved.

At a surprise press conference on June 10, Attorney General Luis Martinez announced that Munguia Payes was among several high-level military officials being investigated in connection with the trafficking of hundreds of guns that should have been destroyed. "It would not be surprising," Martinez said, if those weapons ended up in the hands of the gangs.

Martinez's announcement came just moments after newly inaugurated president Salvador Sanchez Ceren had left a change-of-command ceremony where police lined the streets in his honor. The allegations against Munguia Payes -- a controversial holdover from the previous administration of ex-President Mauricio Funes -- puts the new president in a bind, said Douglas Farah, a senior fellow at the Washington-based International Assessment and Strategy Center.

"There have long been rumors and serious reports that there were arms sales under [Munguia Payes'] watch," he said. "I think it will be an ongoing embarrassment."

At the press conference, Martinez said that Munguia Payes had failed to attend two hearings about the investigation into the arms trafficking case. A third is scheduled for June 18.

"He already has sent his defense counsel, and that reaffirms that he is in the process of investigation," Martinez said, "as are other high-level officials in the armed forces."

Martinez's announcement followed a May 30th showdown in which military officials blocked the attorney general's investigators from entering five garrisons as they attempted to seize documents related to the weapons case.

The documents were required for a full inventory of the nation's arsenal, according to the attorney general. After the investigators failed to get access to them, Martinez went so far as to call Munguia Payes the "most lying and false [Defense Minister] that we have ever known."

Munguia Payes retorted that the attorney general had overreached his boundaries, and that the release of such information would have been a threat to national security.

Munguia Payes served as El Salvador's defense minister from 2009 to 2011, and then was appointed minister of security, a position he held during the forging of El Salvador's gang truce in 2012. An investigation by El Faro revealed that officials under Munguia Payes allowed key leaders of the Mara Salvatrucha (MS13) and Barrio 18 gangs to be moved into lower security prisons, as a possible deal sweetener, but also to allow them to talk to their foot soldiers about the ceasefire.

Last year, El Salvador's Supreme Court ruled it was unconstitutional to have a military officer in charge of the civilian police force, and Munguia Payes was returned to his former post as defense minister. His replacement, Ricardo Perdomo, is a fierce critic of the gang truce who used his position to undermine the process, and the pact foundered. This year, the streets have turned bloody, with killings at nearly pre-truce levels of about 12 a day.

Newly inaugurated President Salvador Sanchez Ceren's decision to retain Munguia Payes came as a surprise to observers inside and outside El Salvador, given the defense minister's ability to attract rumor and controversy.

Farah said that Munguia Payes' role in the truce was one of the likely reasons the new government kept him on. "I think there was a feeling that if they cut ties with Munguia Payes immediately, it would ignite an even more significant wave of gang violence than what you are seeing already."

In the wake of the new accusations against Munguia Payes, however, the Sanchez Ceren administration has announced that it will no longer be lending support to the truce.

If the accusations prove true, it would mean that a key architect of the truce was involved in, or turned a blind eye toward, the selling of military weapons that ended up in gangs' hands.

"This will raise all types of red flags," Farah said.

El Salvador's military has a long history of enriching itself selling everything from gasoline to guns. Intelligence sources say there are no external controls to halt or prevent weapons dealing by military personnel, and that there have been several instances of trafficking during Munguia Payes' watch as defense minister.

In 2011, Salvadoran army officer Hector Antonio Martinez Guillen pleaded guilty in US federal court to terrorism charges after a sting where he offered to sell automatic rifles, ammunition and plastic explosives to undercover agents posing as members of the Revolutionary Armed Forces of Colombia (FARC).

During a yearlong investigation beginning in 2010, Martinez Guillen, also known as "El Capitan," claimed to have access to AK-47 and M-16 assault rifles, and even rocket-propelled grenades. A regional intelligence source told InSight Crime that the initial inquiry into "El Capitan" began after gang members set off several explosions in downtown San Salvador. The plastic explosives and several grenades used in the attacks were eventually traced back to Martinez Guillen and a military weapons cache.

In October 2013, Salvadoran police removed 213 grenades and a Russian shoulder-fired missile launcher that had been stolen from a military weapons depot. The weapons, found buried in a home in the western part of the country, were destined for the notorious Zetas drug cartel in Mexico, and had been smuggled out of the depot in a sand-filled truck. Investigators later accused Army Major Elmer Espinoza Hercules of trafficking the weapons, which were supposed to have been destroyed.  

The regional intelligence source, who asked not to be named because of the sensitive nature of the topic, said that decommissioned weapons are often trafficked.

Broken and disused assault rifles scheduled to be destroyed, he said, are smuggled out in parts and repaired. The reassembled guns are then sold on the black market.

"The trafficking of arms in the military is common," the source said. "Munguia Payes is not the point man, but he has knowledge of what is happening."