Four men who worked for the private military contracting firm formerly known as Blackwater were sentenced in federal court on Monday, more than seven years after they massacred Iraqi civilians in Nisour Square, Baghdad.

A sentencing hearing for the four men – Nicholas Slatten, Dustin Heard, Evan Liberty and Paul Slough – began at 10 a.m. ET in Washington, DC on Monday. Later in the afternoon, the Washington Post reported that Slatten was handed a sentence of life behind bars, while his three ex-colleagues were each dealt 30-year sentences as a result of firearms convictions they were handed last fall..

Six months earlier, a jury convicted Slatten, a former Blackwater security guard, of first-degree murder for his role in the infamous September 2007 ambush.

Together, the men participated in a rampage in the busy Baghdad traffic circle during the height of the Iraq War that left 14 civilians dead. Blackwater, which has since changed its name to Academi, had deployed the guards there along with others to provide diplomatic security services during the American-led military operation.

Attorneys for the former contractors filed an emergency motion on Friday asking the court to delay this week’s sentencing hearing in light of newly discovered evidence they wanted entered in the case, but the request was ultimately rejected that afternoon by US District Judge Royce Lamberth.

Kristen Slough, a wife of one of the former guards sentenced this week, said during a press conference following Monday’s sentencing that attorneys will file motions in the coming days in which they’ll request new trials.

Former Blackwater guards face decades in prison for roles in 2007 shooting of Iraqi civilians http://t.co/hlMkte07gxpic.twitter.com/8RpFScDs17 — Chicago Tribune (@chicagotribune) April 13, 2015

"Defendants, who have been confined since the verdict, do not lightly seek delay, or seek delay for its own sake. But these issues deserve full consideration by the Court: it would be unfair to proceed to impose sentence and enter judgment when this new evidence, disclosed less than two days ago, leaves the trial result fundamentally in doubt," defense lawyers wrote, to no avail.

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The Associated Press said attorneys for the defendants were likely to argue for mercy from the court during Monday’s sentencing, but prosecutors with the federal government asked that the court consider more than just the mandatory minimum 30-year sentences for the three convicted for using military firearms while committing a felony. According to the Washington Post, the government has asked for a 57-year sentence for Slough, who was also convicted of 13 counts of manslaughter and 17 counts of attempted manslaughter; 51 years for Liberty, also convicted of eight counts of manslaughter and 12 counts of attempted manslaughter; and 47 years for Heard, also convicted of six counts of manslaughter and 11 counts of attempted manslaughter. Slatten faces a mandatory prison sentence of life without parole.

“The crimes here were so horrendous – the massacre and maiming of innocents so heinous – that they outweigh any factors that the defendants may argue form a basis for leniency,” the Post quoted from the prosecution’s filing.