This circa 1975 portrait by the U.S. Navy shows Adm. Richard "Dick" Lyon. Lyon, the first Navy SEAL to rise to the rank of admiral, has died. He was 93. Lyon died Friday, Feb. 3, 2017, surrounded by family and friends at his beachfront home in Oceanside, Calif., north of San Diego. He served four decades in the Navy, including World War II and the Korean War. (U.S. Navy via AP)
This circa 1975 portrait by the U.S. Navy shows Adm. Richard "Dick" Lyon. Lyon, the first Navy SEAL to rise to the rank of admiral, has died. He was 93. Lyon died Friday, Feb. 3, 2017, surrounded by family and friends at his beachfront home in Oceanside, Calif., north of San Diego. He served four decades in the Navy, including World War II and the Korean War. (U.S. Navy via AP)

San Diego — Richard Lyon, the first Navy SEAL to rise to the rank of admiral, has died at 93.

Lyon served four decades in the Navy, including World War II and the Korean War, and was among the first U.S. troops to enter Japan after the atomic bomb was dropped.

He went on to work as a Scout intelligence officer in northern China and later served in Korea.

Rear Adm. Tim Szymanski, commander of the Naval Special Warfare Command, called Lyon a legend who was honored with the title “Bullfrog” for being the oldest-serving SEAL. Lyon regularly attended the graduation ceremonies of SEALs.

Lyon died Friday surrounded by family and friends at his beachfront home in Oceanside, north of San Diego, said lifelong friend Kelly Sarber, who met Lyon as a child because her father was also a SEAL.

Sarber recalled photos of Lyon and other SEALs swimming with knives during the elite military team’s beginnings. “He reminded me of James Bond,” she said. “I never saw him lose his cool. I never saw him be nothing but kind and treat people with manners. He was a real class act.”

Lyon enlisted in the Navy in 1942 while studying at Yale University. He was among the first to endure the SEAL training known as “Hell Week” in which trainees spend seven days with almost no sleep, running, swimming and doing other drills. An award-winning swimmer, he continued to body surf in competitions into his 70s, Sarber said. He stayed active in the SEAL community until his death and mentored young SEAL candidates until recently.

“Dick Lyon personifies what it is to be a Navy frogman and Navy SEAL,” said retired Rear Adm. Garry Bonelli, who became a SEAL in 1968. “He had the smarts, the athletic ability and the heart to do special maritime operations.”

Lyon retired from the Navy in 1983 and worked as a retail marketing and financial executive. He served two terms as mayor of Oceanside in 1992 and 1996.

In 2013, Lyon was the recipient of the prestigious Yale University George H.W. Bush Lifetime of Leadership Award.

He is survived by his wife of 41 years, Cynthia Gisslin Lyon; nine children; 14 grandchildren; and two great grandchildren.