Kyle Mullen's cause of death remains under investigation by the Navy
Kyle Mullen
Kyle Mullen
| Credit: Monmouth Hawks

The mother of Kyle Mullen, a Navy SEAL candidate who died on Friday after completing Hell Week training, is mourning the loss of her son.  

"He will be missed every day," Regina Mullen told Fox News on Tuesday, going on to say that their family has "​​lost the light of laughter in our life."

Although he was not actively training at the time of his death, the 24-year-old sailor had just completed Hell Week, which pushes aspiring Navy SEALs to their physical and mental limits.

After Mullen and another sailor, whose name has not yet been released, first "reported symptoms," they were rushed to a local hospital, where Mullen was pronounced dead around 5:42 p.m., the Navy announced in a press release. His cause of death is currently unknown and under investigation by the Navy.  

"We extend our deepest sympathies to Seaman Mullen's family for their loss," Rear Adm. H.W. Howard III, commander of the Naval Special Warfare Command, said in a statement.

The other sailor was hospitalized in stable condition as of Sunday.

Ed Gurrieri, who coached the former college football star at New Jersey's Manalapan High School, said that according to Mullen's mother, the sailor had seemed fine after initially completing training.  

"Everything was great," Gurrieri told ABC affiliate KGTV, recounting a conversation he had with her shortly after she learned of her son's death.

Gurrieri said the sailor's mother is "absolutely devastated" by the loss of her son.

"She took him back and forth to school to games, to everything," he told the outlet. "He was her whole world." 

Kyle Mullen
Kyle Mullen
| Credit: Williams Paul/Icon Sportswire via Getty Images

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Recognizing Mullen's contributions on and off the field, New Jersey Gov. Phil Murphy said the sailor "represented the very best of our state." 

Although a date has not yet been announced, flags in New Jersey will fly at half staff in honor of Mullen in the near future, Murphy said during a press conference on Monday, according to  

"He represented the very best of the state and country," Murphy remakred during the press conference. "He was a legend in athletics and all walks of life."

A memorial fund for Mullen has been created to help cover funeral costs, according to a post on the "Remembering Kyle Mullen" Facebook page, which is run by his family. 

"At 24 years old, Kyle had just completed his first phase of U.S. Navy SEAL training and was beyond excited for all the things he believed lay in wait for his future," read a post on the fundraising page. 

"While we do not have all the tragic details that led up to, during and immediately following his death, the only fact that matters is Kyle is gone forever," the message continued. "His mother, Regina, and brother, TJ, cannot even begin to comprehend what it means to go on without him."