Published: Dec 30, 2013 5:36 PM EST

BOSTON (AP) - The father of a man shot to death by authorities in Florida while being questioned during the Boston Marathon bombing investigation has written President Barack Obama asking for help finding out what happened.
    
Abdulbaki Todashev (TOH'-duh-shehv) says in his letter from Russia son Ibragim Todashev (IH'-bruh-heem TOH'-duh-shehv) knew dead marathon suspect Tamerlan Tsarnaev (TAM'-ehr-luhn tsahr-NEYE'-ehv) through boxing but had no connection to the bombing or any other crime. He says his son voluntarily went to an FBI office in Orlando to speak with FBI agents four times before they showed up at his apartment May 22.
    
Attorney Barry Cohen said Monday the elder Todashev fears a cover-up and is writing to Obama one father to another to make sure that doesn't happen.
    
An Orlando prosecutor is investigating the death. An FBI spokeswoman won't comment.

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