Seifeddine Rezgui has been named as one of the extremists involved in killing 39 people at a beach resort in Sousse, Tunisia.
Here's everything we know about the gunman:
The 23-year-old was an aviation student at Kairouan University
He came from the town of Gaafour in the Siliana region and had reportedly never travelled abroad
Rezgui reportedly disguised himself as a tourist and began firing at holidaymakers using a gun hidden in a beach umbrella
He was said to have been laughing and joking as he sprayed them with gunfire
The student was shot dead by police after the attack
Rezgui was not previously known to the authorities, Tunisia's prime minister said
Islamic State claimed responsibility and used Rezgui's jihadi pseudonym of Abu Yahya al-Qayrawani, according to the SITE intelligence group
Those who knew Rezgui have spoken of their shock at his actions.
Rezgui's uncle said he was "just like the other young men" who liked to play football or go to a cafe after praying in the local mosque.
He liked break dancing and was well-known for entering competitions in the capital Tunis, Ali Al-Rezgui told the Sunday Telegraph.
Referring to the practice of devout Muslim men not shaving their beards, Mr Al-Rezgui said: "He didn't even have a beard."
He added: "We were all shocked when we heard the news and saw his picture, and his mother was devastated."
Neighbours suggested Rezgui may have been brainwashed.
Monia Riahi, 50, who is a neighbour and family friend, described him as "good, good, good!".
She told the Observer: "I've known him since he was small. He was never in trouble with anyone ever. Maybe he was brainwashed or something."
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