WASHINGTON (News Desk) – While people still speculate over the possible factors that prompted Omar Mateen to stage a deadly massacre at Orlando nightclub, the FBI has released an incomplete transcript of the attacker’s conversations with police during the assault.

According to previously available information, Mateen had at least three conversations with police via 911, however the released transcript only partially covers two of these phone calls. FBI officials are also not releasing the audio of the conversations.

Last week, FBI Director James Comey said that, “Omar Mateen called 911 and he hung up after some time, later he called again and had a brief conversation with the dispatcher at the helpline, and finally the dispatcher called him back and they spoke briefly.”

Mateen’s calls and his negotiations with Orlando Police lasted 28 minutes. However, the details released by the FBI contain only “modified” transcript of his conversation with 911 and a “designed” summary of all remaining conversations, reported The Intercept.

In a prior statement, the FBI had said that all transcripts of Omar Mateen’s calls would be released, except those sections in which he dedicated the attack to Islamic State chief Abu Bakr al-Baghdadi.

However, investigators initially claimed that the attacker had also expressed solidarity with the Boston Marathon bombers and Moner Mohammad Abusalha who carried out a suicide bombing in Syria in 2014. Yet, none of this has been mentioned in the transcripts released by the FBI.