El Salvador gang members hand in weapons as part of the truce.

After falling dramatically in the wake of the gang truce, El Salvador's homicide rate began to rise again in May and June, sparking concerns about the sustainability of the truce between the country's two main gangs, Barrio 18 and Mara Salvatrucha (MS-13).

According to police officials, El Salvador had 182 murders in June 2013, up from 166 in the same month in 2012, reported La Prensa Grafica. June also saw an increase of 12 murders from the month before.

During the first half of 2013, the country had 1,045 homicides, down from 1,562 during the same period in 2012. Violence began decreasing in February, hitting a low in April before beginning to rise again in May.

The uptick in homicides in June has caused concern among Salvadoran authorities and led to a meeting between officials from the Ministry of Justice and Public Security and the National Civil Police (PNC) on June 29. Officials were particularly alarmed by the violence during the last weekend in June, which seemed to recall the days prior to the maras' gang truce: 32 homicides were registered between Friday and Sunday.

InSight Crime Analysis

Even with the rise registered in May and June, El Salvador's murder rate for the first half of 2013 represents a significant improvement compared to the previous year; prior to the truce in 2012, the country experienced an average of 14 homicides a day.

However, despite the overall improvement that has been seen this year, the two-month pattern of increasing homicides, coupled with other disturbing trends such as a rise in extortion and disappearances, may undermine both public and institutional faith in the truce. Many in El Salvador, including critical civil society actors such as the Catholic Church, have already expressed skepticism about the future of the truce due to the government's lack of transparency about the negotiations and the exact terms of the gang agreement.

Until now, the government has been able to point to the drop in murders as proof that the truce is working. If homicide rates continue to rise over the next few months the process could find itself in serious trouble.