Students are evacuated from a university campus that was stormed by Islamist militant group Al-Shabaab in Garissa, in this still image taken from video shot on April 2, 2015.[Photo/Agencies]

According to police, Kuno is believed to be very religious and has been a Madrassa teacher for several years. He worked for Al- Haramain Foundation between 1993 and 1995 before the institution was closed. At the time he was known as Sheikh Mahamad.

The suspect later became a teacher and principal at Madarasa Najah in Garissa from 1997 to 2000, where his extremist tendencies became more manifested. He thereafter joined Al-Shabaab after being motivated by the ideology of Islamic Courts Union (ICU) to establish an Islamic statehood in Somalia.

It is reported that majority of the terror attacks in Garissa were carried out by former students of Madarasa Najah. Most of the recruits were drawn from close family members and clan mates.

Police said Kuno used the ideals of caliphate governance to persuade and recruit his students to join the ICU and later to join Al-Shabaab.

The militant group had established a Jabha Unit in every region of Somalia, and Kuno was charged with carrying out attacks against foreign troops.

He is also credited with having an extensive terrorist network within Kenya, particularly at the Dadaab refugee camp. Kuno claimed responsibility for last year's bus attack in Mandera where 28 people were killed.