A second detainee has died after a shooter opened fire on a Dallas Immigration and Customs Enforcement (ICE) facility last week, the Department of Homeland Security confirmed to Fox News.The League of United Latin American Citizens (LULAC) identified the victim as Miguel Ángel García-Hernández, 32, who they said died after being removed from life support following the Sept. 24 sniper attack.García-Hernández leaves behind four young children and his wife, who is expecting their fifth child. MANGIONE, CATHOLIC CHURCH SHOOTER, CHARLIE KIRK SHOOTER, ICE SHOOTER ALL USED ENGRAVED BULLETS"My husband Miguel was a good man, a loving father and the provider for our family," his wife Stephany Gauffeny said in a statement. "We had just bought our first home together and he worked hard every single day to make sure our children had what they needed.""His death is a senseless tragedy that has left our family shattered. I do not know how to explain to our children that their father is gone," she added.García-Hernández was originally from Mexico and in the U.S. illegally. He was arrested by police in Arlington, Texas, on Aug. 8 and charged with driving while intoxicated, evading arrest with a vehicle and fleeing police. That same day, ICE officials filed an immigration detainer against him.Records show García-Hernández had also been charged with failure to identify himself to law enforcement officers in 2011 and 2017. After the 2017 arrest, ICE lodged a detainer but he was released before immigration authorities could take custody.The attack also killed detainee Norlan Guzmán-Fuentes, 37, of El Salvador and wounded Jose Andres Bordones-Molina, an illegal immigrant from Venezuela.DALLAS ICE GUNMAN'S HANDWRITTEN NOTE THREATENED 'REAL TERROR,' FBI REVEALSOfficials said Joshua Jahn, 29, carried out the sniper assault and wanted to incite terror by killing federal agents. Jahn fatally shot himself following the attack.The shooting happened while ICE officers were bringing detainees into the agency’s Dallas facility. ICE sources told Fox News the detainees were inside a law enforcement van when the gunfire erupted. Federal officials said anti-ICE messaging was engraved on rounds found near Jahn’s body.FBI Director Kash Patel said Jahn downloaded a document before the attack titled "Dallas County Office of Homeland Security & Emergency Management," which listed DHS facilities.Between Aug. 19 and Aug. 24, Jahn also searched apps that tracked the presence of ICE agents, Patel said. In the hours before the shooting he looked up ballistics information and the "Charlie Kirk Shot Video."CLICK HERE TO GET THE FOX NEWS APPInvestigators also recovered a handwritten note in which Jahn wrote: "Hopefully this will give ICE agents real terror, to think, ‘is there a sniper with AP rounds on that roof?’" Patel said evidence gathered so far indicates a "high degree of pre-attack planning."Fox News’ Adam Sabes and The Associated Press contributed to this report.