Anti-terrorism police are facing a new ghost in the fight against terrorism; that of a kamikaze.
Multi-agency teams investigating the terrorist attack at dusitD2 in Nairobi say the case of the kamikaze who participated in the attack was the first to be registered in the country.
They are now trying to establish whether there is a terrorist cell composed of suicide bombers who target the country, or if it is an isolated case.
It is unclear whether the 25-year-old al-Shabaab agent Mahir Khalid Riziki, who blew himself up at dusitD2, is one of many others in a cell in Somalia.
"We do not know if there are others left and what their next mission is," a security official said.
Riziki was a recruit of Al-Shabaab born in Mombasa, who had gone to Somalia for training that lasted almost five years.
The investigators who handle the matter say they believe Riziki used drugs during the period when he was radicalizing in Somalia.
The Riziki accomplices used during the attack had what the police believed were drugs. It is assumed that they have swallowed the drugs to gather courage.
Part of Riziki's family is under police interrogation to reveal any information that can help get more clues to terrorists.
Police squads were sent to Mombasa, Mandera, Kisumu, Isiolo and Moyale to pursue leads on the likelihood of more kamikaze.
Agents investigating the incident say that while he was attending prayers at the Masjid Musa mosque in Mombasa, Riziki met Ramadhan Hamisi Kufungwa, the man who recruited him.
Kufungwa is now in Somalia fighting with Al-Shabaab.
For almost a decade, the Musa mosque has been associated with radicalization and religious violence.
But in recent times, the intervention of governmental security agencies and the administration of Mombasa County has led to the removal of radical elements, which have been replaced by more liberal clerics.
The most radical followers who used to pray in the mosque fled to Somalia. It is not the first time that Riziki enters the security radar.
The police say that in 2014 he was part of a killing team charged by Al-Shabaab to assassinate security personnel on the coast.
It was then that his name was included in the list of the most wanted and a handful of millions of Sh2 put him in the head.
In October 2014, Riziki was involved in the killing of a police officer at the Royal Court Hotel.
His gang was led by Ismael Mohamed Shosi aka Ismael Mmanga, a former resident of Bondeni, in Mombasa County.
Shosi was killed by security agencies on September 27, 2016 in his hiding place in Mwandoni. He resisted the arrest and hired the police in a gun battle.
Riziki escaped to hide in Tanzania in November 2014 after the security agencies published his photo on the posters of Mombasa, calling him wanted.
It is in Tanzania that most Kenyan recruits were lured with false promises of scholarships, only to be redirected to Somalia for military training.
At the beginning of 2015, Riziki had told his family that he had moved to Somalia, where he was undergoing Al-Shabaab training.
According to the police, in November and December of last year, while he was doing his final training in Somalia, Riziki would have regularly contacted his wife Suhaila Mwalim Bakari.
He would like to find out how he was. Ms. Suhaila never reported her husband to the police, which is why she was arrested.
When his coaches were sure they were ready for the mission, he was sent back to Kenya.
On January 13, Riziki entered Kenya via Elwak in the county of Mandera, then in Takaba, and boarded a Moyale Raha bus tied to Nairobi in Marsabit.
When he arrived, he immediately proceeded to Muchatha, Kiambu, to connect with the leader of the attack, Ali Salim Gichunge aka Faruk.
Riziki was to receive instructions on his role in the attack planned by Gichunge.
It is believed that he met Gichunge in Somalia, where they both trained.
On the day of the attack, Riziki would have arrived at the scene of the attack first, but was constantly in communication with Gichunge, taking instructions and updating him on what he was doing.
"The attack strategy was for him to blow up his suicide jacket and kill people at the Secret Garden restaurant as he signaled the attackers coming in. Then, while people were looking for safety at the main entrance of 14 Riverside Drive , the other four strikers should have embarked on a killing spree against the fleeing crowd, "says a security source.
A communication error
"Fortunately, there was a communication error between the suicide bomber and the foot attackers, which gave way to a good number of people to escape," said an officer The standard.
A CCTV footage examined by security agencies captures the moment when Riziki blew himself up. It is located next to the Secret Garden restaurant inside the complex for about two minutes, inspecting its planned objectives and updating Gachunge.
Two people, one of whom is a cook in the restaurant, are seen passing by Riziki, escaping death by a whisker. Riziki then says his last prayers and exactly at 15:28 he blows himself up.
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