Kenyan police have named homegrown militant Islamist Mohamed Mohamud, a quietly spoken former teacher, as the alleged mastermind of the massacre of 148 people in a university in Garissa.
Known also by the alias Kuno, as well as 'Dulyadin' and 'Gamadhere' - meaning "long armed" and "ambidextrous" - the alleged Shebab member is also wanted in connection with a string of recent cross-border killings and massacres in Kenya's northeastern border region.
Police have offered a 20 million shilling ($215,000, 200,000 euro) bounty for information leading to his capture.
Kenya's ethnic Somali region is also claimed by the Shehab as part of Somalia itself, and has long been lawless, including the brutal secessionist 1963-1967 "Shifta war".
The poster of Mohamud shows a slender man with a short beard.
An AFP correspondent who met him in the Somali capital Mogadishu in 2008 and 2009, when the majority of the city was under Shebab control, said Mohamud was a well-known and feared commander.
Reaching into Kenya
Mohamud, however, also appeared in person as educated as well as "quiet and gentle".
In the murky world of Somali armed groups, politics and clan loyalties, Madobe's forces helped Kenyan forces seize the key port of Kismayo in 2012.
But under pressure on their home soil, the Shebab have reached into Kenya to carry out attacks and find recruits among disaffected youth in the Muslim-majority coastal and northeast regions.
In November, the Al-Qaeda-affiliated group claimed responsibility for holding up a bus outside Mandera, separating passengers according to religion and murdering 28 non-Muslims.
Ten days later, 36 non-Muslim quarry workers were also massacred in the area.
A Shebab statement yesterday warning Kenyans of further bloodshed, said the gunmen carried out the Garissa attack in revenge for the "systematic persecution of the Muslims in Kenya".
Attacks cited include Kenya's 1984 Wagalla massacre, when Kenyan troops trying to put down local conflict killed an unknown number of people - officially less than a hundred, while others claims up to 5,000 people.
Cash rewards for other Shebab commanders - offered by the US, and unlike Mohamud's bounty, in their millions of dollars - are believed to have led to information that have resulted in a series of air strikes in Somalia to assassinate them.
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