U.S. officials have now identified a Navy SEAL who was killed Tuesday in a firefight with ISIS in northern Iraq.

Charlie Keating IV, 31, was the grandson of prominent Arizona financier Charles H. Keating Jr., who went to prison after the savings and loan scandal in the 1980s.

The elder Keating died in 2014 at age 90.

Keating IV was a native of Arizona, a former high school track star in Phoenix and reportedly engaged to be married in the fall. 

"Like so many brave Americans who came before him, Charlie sacrificed his life in honorable service to our nation for a cause greater than self-interest, which we can never truly repay," said Sen. John McCain in a statement.

He was reportedly close with his grandfather, once telling a local newspaper that schoolchildren made fun of him because of the prison sentence.

"What happened in the past, I really don't care. I'm really close to him," the younger Keating told the Arizona Republic in May 2004 when he ran in the Class 4A state track and field championships in suburban Mesa, Arizona, and his grandfather watched him compete for the first time.

Keating IV went on to run cross country and track at Indiana University from 2004-06 before joining the Navy. 

KTVK reported:

Keating's former track coach at Arcadia said he has kept in touch with Keating through Facebook over the years and he is heartbroken by the news.

"I'm devastated. I'm crushed. I'm trying to hold myself together," said Rob Reniewicki, Arcadia High School track coach. "I've known the parents. I've known the family. His brother's a Navy SEAL as well."

He was planning to get married in November, according to Reniewicki.

“I have a wedding invitation - 'save the date' - on my refrigerator,” he said.

Keating was shot and killed by small arms fire north of Mosul, where U.S. soldiers are serving in an advisory capacity to Kurdish forces.

He is the third American soldier killed in the battle against ISIS since October.

AP contributed to this report.

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