Kenyan police are patrolling around the home of President Barack Obama's step-grandmother in Kenya after al Shabaab, a Somalia-based extremist group with ties to al Qaeda, issued a personal threat against her.

As ABC News reports, Sarah Hussein Obama seemed unconcerned over the threat, despite the fact that the extra security around her home had increased. "My life has not been affected in any way," the elder Obama, 88, said. "It has not restricted my movement. If the government has decided to bring more security personnel, we are OK with it."

As the third wife of Obama's paternal grandfather, Sarah is not related to the president by blood, but he affectionately refers to her as "Granny," the New York Post reports.

The threat is neither new nor credible, CBS News quotes an expert involved in security matters at the U.S. Embassy in Kenya as saying, and local police added security only out of an abundance of caution. A longtime al Qaeda affiliate, al Shabaab has been linked to piracy, beheadings, and terror links to Somali communities in the United States.

The threat is just one of several issued by radical organizations after bin Laden was killed by U.S. special forces in Pakistan May 1. Authorities believe the greatest threat to the U.S. is posed by al Qaeda in the Arabian Peninsula. "Do not dismiss this battle so easily, and give your people false hope that if you kill Osama that it is over," Nasir al-Wahishi, a leader of the Yemen-based group, is quoted by ABC News as saying Wednesday. "What is waiting for you is far greater and more dangerous, and you will then count your regrets, wishing for the days of Osama."