Before he released a video declaring war against Kenya on behalf of Somalia militant group Al-Shabaab, few Kenyans had heard of Sheikh Ahmed Iman Ali.
Last week, Al-Shabaab appointed Sheikh Ali as the de facto leader of Kenyan Al-Shabaab fighters in Somalia. Recently, Sheikh Ali called for revenge attacks against Kenya.
Interviews with those who know Sheikh Ali, a former chairman of Muslim Youth Centre (MYC) in Pumwani, Nairobi, say he has been controversial since his days at Jomo Kenyatta University of Science and Technology where he graduated with a degree in engineering.
Born either in 1973 or 1974, Sheikh Ali presents security agents with something new in the fight against terrorism.
Those who know him say he was a charming preacher with a fanatical following among various Kenyan communities.
He is said to have the ability to attract financial support and followers from countries like the US and Europe.
Britons Natalia Faye Webb and Jermaine Grant arrested in Kenya over claims of links to terrorism were reportedly close to him. His mix of scripture and vitriol made him differ with Imams close to him.
They say he was propagating the idea of forcing people to join Islam through his insistence that "through violence they can understand Islam."
In 2007, he masterminded the ouster of an executive committee of Pumwani Riyadha Mosque when he led the youth in throwing out five officials over alleged corruption and mismanagement claims.
It is not clear when he graduated from the university but his associates gave 2001 as the probable year.
The university refused to divulge the details saying that such information was "highly confidential" even when the Nation insisted that it could help avert possible terrorist attacks especially in establishing the links he made as a student.
"It is a matter of national security. Anti-terror police came here and said that we should not give out information about him," a senior official at the Jomo Kenyatta University of Science and Technology told the Nation.
After university, he worked for Shell and Mobil as an engineer. Al-Shabaab said that they had raised Sheikh Ali's status to "Supreme Amiir."
They say that he was following in the footsteps of Fazul Mohammed, the former leader of Al-Qaeda's operations in East Africa.
Fazul also served as a senior leader in Al-Shabaab. Sheikh Ali formed MYC in 2006 under the slogan "preference for others" to provide the youth with religious counselling.
A report by the UN Somalia and Eritrea Monitoring Group indicates that Sheikh Ali was central in the recruitment of non-Somalis in Nairobi to join Al-Shabaab fighters in Somalia.
The report says Al-Shabaab "has extensive funding, recruiting and training networks within Kenya" and has "established connections with jihadist groups across the continent."
The UN investigation that focused on the youth centre claims that the organisation was involved in the recruitment of Al-Shabaab operatives.
Officials of MYC have since distanced themselves from Sheikh Ali and the recruitment of Kenyans to join Al-Shabaab.
"Officially, the MYC Constitution defines the group as a 'community based-organisation' that aims to provide youth with religious counselling... In practice, members of the group openly engage in recruiting for Al-Shabaab in Kenya," the report claims.
It continues: "Ahmed Iman's success in recruiting fighters and mobilising funds for the cause, appear to have earned him steady ascendancy within Al-Shabaab. The Monitoring Group believes that he now intends to conduct large-scale attacks in Kenya."
A fortnight ago, Al-Shabaab released a propaganda video declaring war against Kenya. The video was reportedly released by Sheikh Ali.
In the recording entitled 'If they seek your help in religion, it is your duty to help them', he says war should now be waged in Kenya in response to the military operation in Somalia.
"Kenya has declared war against Somalia and Jihad should now be waged inside Kenya which is legally a war zone," Sheikh Ali says in the video.
The video, which was initially posted on YouTube, has since been withdrawn although it can still be viewed on other social media networks.
One of his most controversial roles that propelled him to the public limelight as a terror mastermind was as secretary of the Pumwani Riyadha Mosque building committee, which is embroiled in claims of funding terrorist activities.