Samantha Lewthwaite, the so-called “White Widow,” is now the right hand of al Shabaab leader Ahmad Umar and has allegedly orchestrated the deaths of more than 400 people in the region, a Somalia security chief told the Daily Mirror. Lewthwaite, a British-born Muslim accused of terrorism, is suspected of masterminding last month’s terror attack on a Kenyan university which killed 148 students.

“She is one of the most important figures in the terror group,” a top officer at Somalia’s National Intelligence and Security Agency told the London tabloid on Sunday night. “We think this lady is sitting at the right hand of the leader directing attacks.”

The “White Widow” has quickly risen through the ranks of the Somali-based terror group after many al Shabaab leaders were killed in drone attacks, the security chief alleged. She has also used bribes to successfully recruit teenagers and women as suicide bombers in the Somali capital Mogadishu.

“She does not carry out attacks herself as she is too important but is responsible for many, many deaths – hundreds,” the Somali security chief, who asked not to be named, told the Daily Mirror. “She uses children to kill for her after giving money to their families.”

Somali security officials suspect Lewthwaite is hiding out near the town of Haaway in southern Somalia, an al Shabaab stronghold. Last year, she reportedly married an al Shabaab warlord known as Hassan Maalim Ibrahim or Sheikh Hassan, the Daily Mirror said.

Lewthwaite, 32, is known as the “White Widow” because she is the widow of a suicide bomber who killed dozens in a terrorist attack on London’s transportation system in July 2005. She has since fled the country and was allegedly behind the 2013 attack on a Kenyan mall in Nairobi which killed 67 people.

Last year, a Russian news service alleged that Lewthwaite was shot and killed by a Russian sniper in eastern Ukraine. The claim was not officially confirmed and the Regnum news agency did not name its source. British officials also said they had no evidence of Lewthwaite in Ukraine at the time of the report.

“We share all our information with British agents here in Mogadishu. They are here to keep an eye on the lady and other Britains in Somalia,” the Somali security chief told the tabloid newspaper.

Al Shabaab is an offshoot of the now-defunct Islamic Courts Union and pledged loyalty to the al Qaeda terrorist organization in 2012. The Islamist extremist group wants to overthrow the Somali government and impose its own harsh enforcement of Shariah law in the East African country. Al Shabaab launched its insurgency on major Somali cities by 2009 and has orchestrated cross border attacks. Much of rural Somalia is controlled by the militants.