NCIS star Mark Harmon pays heartbreaking tribute to co-star David McCallum

Mark Harmon has paid tribute to his former co-star David McCallum following his death.

The news broke this week that the Scottish actor had sadly passed away at the age of 90.

Best known for starring in the spy series The Man from U.N.C.L.E., McCallum also appeared in over a dozen seasons of the hit drama NCIS.

In the series, he played Donald 'Ducky' Mallard, the show's medical examiner.

And following news of the actor's death, NCIS co-star Harmon, who famously played special agent Leroy Jethro Gibbs, has paid his own heartfelt tribute to him.

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Sharing his statement with TVLine, Harmon said it was a privilege to work with McCallum.

"I was in awe when I first met him and all of us on the show were honored to have toed a mark opposite him," he said.

"My condolences go out to [David's wife] Katherine and his family."

His words come after the team behind NCIS share their own statement on social media.

"We are deeply saddened by the passing of David McCallum and privileged that CBS was his home for so many years," the statement read.

"David was a gifted actor and author, and beloved by many around the world. He led an incredible life, and his legacy will forever live on through his family and the countless hours on film and television that will never go away."

It went on: "We will miss his warmth and endearing sense of humor that lit up any room or soundstage he stepped onto, as well as the brilliant stories he often shared from a life well-lived.

"Our hearts go out to his wife Katherine and his entire family, and all those who knew and loved David."

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McCallum, who was born in Glasgow but had lived in the US for many years, becoming a citizen in 1999, died on 25 September.

It was revealed at the time that the actor had died from natural causes at New York Presbyterian Hospital.

In a statement announcing the sad news, a spokesperson for CBS said: David was a gifted actor and author, and beloved by many around the world.

"He led an incredible life, and his legacy will forever live on through his family and the countless hours on film and television that will never go away."

McCallum is survived by wife Katherine, their son, Peter, and daughter, Sophie, and by his sons Val and Paul from his first marriage.

His third son, Jason, who he had with his first wife Jill Ireland, died in 1989.