Ten people were killed in two separate incidents in El Salvador Friday, marking a bloody New Years Day for the country.

The first incident occurred in the eastern municipality of San Miguel and involved several men wearing military-style outfits who attacked two homes during New Years' celebrations, killing five people in total: three men, two women, and a child, according to the Latin American Herald Tribune. The hitmen are suspected to be gang members, with the killings having occurred in an area controlled by the notorious Mara Salvatrucha (MS-13) gang.  

The second incident occurred in the southwestern town of Olocuilta, where five alleged gang members were killed in retaliation for having opened fire at police at a highway checkpoint, Reuters reported.

2015 marked El Salvador's most violent year since the country's 1980-1992 civil war, with the homicide rate surging up by 70 percent from 2014, according to The Globe and Mail. The total population of El Salvador is 6.4 million, which amounts to around 104 murders per 100,000 people.

Part of the increase in murders is connected to the end of a multi-year truce between the MS-13 and Barrio 18 gangs, as well as their ongoing clashes with police security, reported TeleSUR.

MS-13 and Barrio 18, the two major rival gangs in El Salvador, both have origins in the Salvadoran exiles who fled the country's civil war during the 1980s and were temporarily resettled in Los Angeles. When they were sent back to El Salvador at the war's end in 1992, gang culture came with them and evolved to include the transnational drug cartels that operate throughout the region, The Guardian explained in September. 

With the surge in violence through 2015, El Salvador is set to overtake Honduras as the country with the world's highest murder rate, according to InSight Crime.