(ATTN: ADDS details of soldier's suicide note, initial probe results in paras 4-6)
SEOUL, July 9 (Yonhap) -- An Army soldier jumped off a Han River bridge to his death, officials said Tuesday, after his unit came under fire for failing to detect a North Korean boat's arrival at a South Korean port last month.
The 21-year-old private first class from the Army's 23rd division in Samcheok, Gangwon Province, threw himself into the Han River in Seoul on Monday night. After being rescued, the solider, whose identity was withheld, was rushed a nearby hospital, but died soon after, Col. Jeon Ha-kyu said.
The man was on a nine-day leave of absence that started July 1.
While an investigation is under way to determine the motive of his suicide, the initial probe by military police found that he had been rebuked by a senior officer since April for his poor handling of his duties.
In a suicide note he left in his cellphone, the soldier described difficulties in adapting to military life away from his parents and reproached himself for incompetence, according to investigators.
The draftee did not mention anything about the North Korean boat case in his note, they added.
The soldier was on duty at a coastal post on the afternoon of June 15 after the small wooden boat carrying four North Koreans arrived at the Samcheok port undeterred earlier in the day.
He was in charge of writing a log and reporting situations to higher ranks at that time.
"He had not been under any military investigation over the North Korean boat case. ... Opening all possibilities, we will thoroughly look into the cause of his death and any ties between this tragedy and the boat incident," the colonel told a regular briefing.
Expressing her regret over the death, defense ministry spokesperson Choi Hyun-soo stressed the military's principle that it will not make enlisted soldiers responsible for the security lapse over the boat case.
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