After another series of brutal murders, the street gang called MS-13 turned the US public's attention to its activities. The last crime was committed on Monday in New York's Long Island neighborhood, where four men's bodies were found, of which three were teenagers.

Trump's administration is blaming Obama

President Donald Trump publicly described the gang as "bad", and the chief state attorney and justice minister Jeff Sessions swore to destroy it. Both of them have been blaming Barack Obama's policy towards immigrants in the US cities.

But who are actually MS-13 members, and whether Obama is responsible for their ups and downs, BBC researched.

The gang was created long before the Obama administration, even during the mandate of Ronald Reagan in the 80s of last century. Established in the immigrant districts of eastern Los Angeles, the MS-13 roots draw from El Salvador, from which many people are fleeing because of the bloody civil war. Apart from Salvadorans, band members come from some other Central American states such as Honduras, Guatemala, and Mexico.

Their name MS-13 is a combination of words Mara (band), Salva (for Salvador), and trucha, which BBC roughly translated as "street resource", while 13 indicates the ordinal number of letter M in the alphabet. They earned their reputation of extremely dangerous and abusive group, because of their killings with the use of machete, rape, and torture of the various people.

Although they were established in quarters of L.A. dominated by Mexican gangs, the MS-13 has grown and expanded to 46 federal states, according to FBI estimation.

One of the largest crime groups in the state

Because of the rapid expansion, the US Finance Ministry has been considering them as an international criminal organization since 2012, making them the first street gang to be "honored" to be in the same company with much larger criminal organizations such as Yamaguchi-Gumi, Japanese yokes Organization, the Italian mafia Camorra, the 'Ndrangheta' or Mexican narcotics CJNG and Los Zetas.

MS-13 recruits their members mostly from the ranks of teens from poor families (on a regular street banner), and to become a member, one must endure brutal beating in a "symbolic" duration of 13 seconds and commit a crime, usually a murder. If the entry seems tough, getting out of the gang is almost impossible. Large tattoos across the chest, even head, mark members for the rest of their lives and some factional gangs are killing members who are trying to escape that life.

In 2008, FBI estimated that MS-13 in the US alone has between 6,000 and 10,000 members, making it one of the largest crime groups in the state. But their number is even higher in Central America, especially El Salvador, the FBI says. Namely, during extensive police actions in the 1990s, hundreds of gang members were expelled from the United States and in the states where they came from, they founded a kind of subsidiary. According to estimates by US security services, there are 60,000 members of MS-13 in Central America today.

What separates them from other gangs, apart from their number and diversity, is their inclination towards violence, as has been said before. They are linked to the killing of two schoolchildren in New York in March this year, who were beaten with baseball sticks and cut into a mache, allegedly due to some "minor" disarray.

Because of this crime, four members of the gang are awaiting the end of their trial.

In addition to that murders, in the same month gang members kidnapped three teenagers who were raped after. The defendants of this foul crime, at their first appearance in court, waved the cameras through laughter, not showing any signs of remorse.

Even though Trump's administration is accusing Obama of the existence of this gang, the FBI has already labeled them as a security threat in 1994, and special units have been formed to capture, prosecute and expel the members of MS-13.