A Hudson Valley Army veteran and 9/11 first responder died from a 9/11 related illness.

Mark Gado, 70, of Hopewell Junction, died on Sunday after a battle with a very long illness, according to his obituary.

Gado was a detective with the City of New Rochelle Police Department for 29 years. He was among those who responded to Ground Zero following the 9/11 terrorist attacks and participated in rescue efforts there until October 2001, his wife told the New York Post.

“He gave them his life,” she said. “He didn’t have to go, [but] he saw a problem and he went. That was just Mark," Gado's wife, Jill Gado, said to the New York Post. “He didn’t talk about 9/11. It was very, very traumatic."

Gado was an Army combat veteran in the Vietnam War and also worked with the Department of Drug Enforcement Administration. He later wrote several true crime books.

Mark was born in the Bronx in 1948. He and his childhood sweetheart, Jill, were married in 1971 and raised two children together. The family now has four grandchildren.

A wake will be held on Friday from 4 p.m. to 8 p.m. at McHoul Funeral Home on Route 82 in Hopewell Junction. In lieu of flowers or gifts, the family is asking for donations to the Wounded Warrior Project in his honor.

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