Officials confirm attacker 's identity through forensic testing . The suspect is a white male in his 20s with short hair and wearing a black baseball cap, according to the FBI. Authorities have detained three people for questioning over the attack , semi-official media reports .
Officials confirm attacker 's identity through forensic testing . Terror group claims responsibility and criticizes Turkey for its ties to the West . `` E. Alisan Sanli has become a martyr , '' the group 's website says . Authorities have detained three people for questioning over the attack , semi-official media reports .