The Swedish side have released a statement expressing their "shock and sorrow" at the news of Ivan Turina, who died in his sleep on Wednesday
The Allsvenskan side released a statement to announce that the former Croatia international passed away on Wednesday and pledged their support to his family.
"It is with great sorrow and shock that AIK can confirm goalkeeper Ivan Turina died during the night between Wednesday and Thursday," the statement read.
"AIK's thoughts are with Ivan's wife and two daughters, as well as his other relatives and friends.
"AIK have informed the players about what has happened. We ask people to respect everyone concerned and allow them the chance to grieve in peace."
Police spokesman Patrik Nuss informed Swedish newspaper Aftonbladet on Thursday that "there were no suspicions of crime" surrounding the player's death.
Club sporting director Bjorn Wesstrom added: "Ivan's heart stopped beating during the night, unfortunately doctors have not brought him back to life. It is so terrible."
The former Dinamo Zagreb keeper was known to have been born with a minor heart defect, although the problem was never considered serious or life-threatening.
Turina made more than 180 apperances at club level during his career, and earned one senior cap for Croatia in 2006. He leaves behind a wife and two one-year-old daughters.