By Brian Vitagliano
(CNN) -- A 15-year-old Connecticut boy who shot and killed himself last week with the family shotgun had sustained years of bullying, friends said Monday.
Bart Palosz committed suicide August 27 after attending the first day of his sophomore year at Greenwich High School in Greenwich, Connecticut.
Friends who knew Bart, a Polish immigrant, told CNN he was the target of bullies due to his size -- the teen was 6 feet, 3 inches tall -- and Polish accent. The friends described him as "a little awkward in his body" but said he was a "giant sweetheart" who related more with adults than his peers.
Lisa Johnson's 13-year-old son Izzy was good friends with Bart and the Palosz family. She gave one of several eulogies at his funeral Friday, saying, "Bart was one of the kindest kids I had ever met. ... It was a life-changing friendship for Izzy. Bart was two years older, and he was so kind, funny, and refreshingly different from any kid Izzy had ever been around. Our family is absolutely devastated by the loss of Bart in our lives."
Johnson confirmed to CNN that Bart had indeed been bullied for years and said that his family had done everything they could to inform the school district of the situation.
Kim Eves, communications director for the Greenwich School District, said the district is "looking at the entire history in his experiences in our school that is an ongoing investigation."
Johnson said that Bart did not publicly exhibit any signs of a child in trouble.
But after Bart's suicide, several posts came to light on Palosz's social network site on Google Plus that appear to reveal his internal struggles.
"Hey if I were to stab my eye out due to school caused insanity, who would miss me?" he posted in June alongside a photo of himself with a knife next to his eye.
Another post in June appeared to indicate he had attempted suicide by ingesting lighter fluid.
The following month he posted, "I notice if I sound sad I'm normal and if I act happy, cheerful, and 'normal' there is a high chance that I will try to poison myself, cut myself, commit suicide, or jump in front of a truck :)"
A preliminary investigation by the Greenwich Police Department found that the gun Bart used to kill himself was family owned and had been stored inside a gun locker in the home.
"The incident continues to be investigated by members of the Greenwich Police Detective Division," a police statement said, declining to provide further information.
Bart's family has flown back to Poland to bury him and was not available for comment Monday, Johnson told CNN.
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