WASHINGTON (KFDX/AP) — President Donald Trump on Tuesday pardoned four former government contractors, including a Texoma native, convicted in a 2007 massacre in Baghdad that left more than a dozen Iraqi civilians dead, including two young boys, and caused an international uproar over the use of private security guards in a war zone.

Dustin Heard was born in Olney. He joined the United States Marine Corps in October of 2000. After being honorably discharged from the United States Marine Corps in 2004, Heard was vetted to join Blackwater Security Consulting, a private military company contracted by the State Department to provide security services in Iraq. Heard and two other men, Paul Slough and Evan Liberty, opened fire at the crowded traffic circle in September 2007.

FILE – In these various file photos, Blackwater guards, from left, Dustin Heard, Paul Slough, Evan Liberty and Nicholas. A federal judge won’t give a new trial to four former security contractors convicted in a mass shooting of Iraqi civilians in 2007. (AP Photo/File)

Prosecutors asserted the heavily armed Blackwater convoy launched an unprovoked attack using sniper fire, machine guns, and grenade launchers. Defense lawyers argued their clients returned fire after being ambushed by Iraqi insurgents. They were convicted in 2014 after a months-long trial in Washington’s federal court, and each man defiantly asserted his innocence at a sentencing hearing the following year.

Blackwater Worldwide security guard Dustin Heard leaves federal court in Washington, Tuesday Jan. 6, 2009, after pleading not guilty to manslaughter charges. (AP Photo/Jose Luis Magana)

Heard, Slough and Liberty were sentenced to 30 years in prison, though after a federal appeals court ordered them to be re-sentenced, they were each given substantially shorter punishments. A fourth, Nicholas Slatten, whom prosecutors blamed for igniting the firefight, was sentenced to life in prison.

Heard’s lawyer, David Schertler, said they were “thrilled and grateful” for the pardon. “We have always believed in Dustin’s innocence and have never given up the fight to vindicate him. He served his country honorably and, finally today, he has his well-deserved freedom.”

The Blackwater firm was founded by Erik Prince, an ally of Trump and the brother of Education Secretary Betsy DeVos. It has since been renamed.