Anti-terror police are confronting a new ghost in the terrorism fight; that of a suicide bomber.
Multi-agency teams investigating the terror attack at the dusitD2 Nairobi say the case of the suicide bomber who participated in the attack was the first to be recorded in the country.
They are now trying to establish if there is a terrorist cell made up of suicide bombers targeting the country, or if it was an isolated case.
It is not clear if 25-year-old Al-Shabaab operative Mahir Khalid Riziki, who blew himself up at the dusitD2, is one of many others in a cell in Somalia.
“We don’t know if there are any others remaining and what their next mission is,” said a security official.
Riziki was a Mombasa born Al-Shabaab recruit who travelled to Somalia for a training that took almost five years.
Detectives handling the matter say they believe Riziki used drugs for the period he was being radicalised in Somalia.
The vehicle Riziki’s accomplices used during the attack had what police believe were drugs. They are alleged to have swallowed the drugs to gather courage.
Part of Riziki’s immediate family is under police interrogation to reveal any information that may help in getting more clues about the terrorists.
Police teams have been dispatched to Mombasa, Mandera, Kisumu, Isiolo and Moyale to pursue leads on the probability of having more suicide bombers.
Officers investigating the incident say it is while attending prayers at Masjid Musa Mosque in Mombasa that Riziki met Ramadhan Hamisi Kufungwa, the man who recruited him.
Kufungwa is now in Somalia fighting alongside Al-Shabaab.
For almost a decade, the Musa mosque has been associated with radicalisation and religious violence.
But of late, intervention by Government security agencies and the Mombasa County administration has led to removal of the radical elements, who have been replaced with more liberal clerics.
Most radical followers who used to worship at the mosque have fled to Somalia. It is not the first time Riziki has come under the security radar.
Police say in 2014, he was part of a killer squad tasked by Al-Shabaab to assassinate security personnel at the coast.
It was then that his name was put on the most wanted list and a bounty of Sh2 million put on his head.
In October 2014, Riziki was involved in the killing of a police officer at Royal Court Hotel.
His gang was led by Ismael Mohamed Shosi alias Ismael Mmanga, a former resident of Bondeni, Mombasa County.
Shosi was killed by security agencies in September 27, 2016 at his hideout in Mwandoni. He had resisted arrest and engaged police in an exchange of fire.
Riziki fled to hide in Tanzania in November 2014 after security agencies posted his photo on Mombasa billboards, terming him wanted.
It is in Tanzania that most Kenyan recruits were being lured with fake promises of scholarships, only to be rerouted to Somalia for military training.
In early 2015, Riziki had told his family that he had relocated to Somalia, where he was undergoing training by Al-Shabaab.
According to police, in November and December last year, while undertaking his final training in Somalia, Riziki would regularly contact his wife Suhaila Mwalim Bakari.
He would want to find out how she was doing. Ms Suhaila never reported her husband to the police, and that is why she was arrested.
When his trainers were sure he was ready for mission, he was sent back to Kenya.
On January 13, Riziki sneaked into Kenya through Elwak in Mandera County, then to Takaba, and boarded a Nairobi-bound Moyale Raha bus in Marsabit.
When he arrived, he immediately proceeded to Muchatha, Kiambu, to link with the attack leader, Ali Salim Gichunge alias Faruk.
Riziki was to get instructions on his role in the planned attack from Gichunge.
It is believed he had met Gichunge in Somalia, where they both trained.
On the day of the attack, Riziki reportedly arrived at the attack scene earlier, but was constantly communicating with Gichunge, taking instructions and updating him on what he was up to.
“The attack strategy was for him to detonate his suicide vest and kill people at the Secret Garden restaurant while signalling the incoming attackers. Then, as people scampered for safety towards the main entrance of the 14 Riverside Drive, the other four attackers were supposed to embark on a killing spree targeting the fleeing crowd," says a security source.
"Thankfully, there was a miscommunication between the suicide bomber and the foot attackers, which gave some room for a good number of people to escape,” an officer told The Standard.
A CCTV footage being scrutinised by security agencies captures the moment Riziki blew himself up. He stands next to Secret Garden Restaurant within the complex for about two minutes, inspecting his intended targets and updating Gachunge.
Two people, one of them a cook at the restaurant, are seen walking past Riziki, escaping death by a whisker. Riziki then says his final prayers and at exactly 3:28pm blows himself up.