(ERBIL, IRAQ) A few weeks ago, a person inside Mosul began to send text messages to Iraqi military intelligence in Baghdad.

Abu Bakr al-Baghdadi, the leader of Islamic State, “has become intemperate,” said the early November message, written by an informant inside the city who has contact with the group but is not a member of it.

“He has cut down on his movements and neglects his appearance,” the message read. “He lives underground and has tunnels that stretch to different areas. He doesn’t sleep without his suicide bomber vest so he can set it off if he’s captured.”

The text message, which Reuters has seen, was one of many describing what was happening inside Islamic State as Iraqi, Kurdish and American troops began their campaign to retake the group’s northern Iraqi stronghold of Mosul.

The texts, along with interviews with senior Kurdish officials and recently captured Islamic State fighters, offer an unusually detailed picture of the extremist group and its leader’s state of mind as they make what may be their last stand in Iraq. The messages describe a group and its leader that remain lethal, but that are also seized by growing suspicion and paranoia.

Defectors or informants were being regularly executed, the person texted. Baghdadi, who declared himself the caliph of a huge swathe of Iraq and Syria two years ago, had become especially suspicious of people close to him. “Sometimes he used to joke around,” one text said. “But now he no longer does.”

Reuters copy