The militants who led the attack on Nairobi's Westgate Mall reportedly rented a shop there in the weeks before they killed at least 67 people in the complex.
Senior security sources told BBC News that as renters in the mall, the militants had access to service elevators that enabled them to stockpile weapons and ammunition, allowing them to re-arm quickly during the attack.
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While the Kenyan government has yet to confirm how the militants were able to have full knowledge of the layout of the mall, it is investigating the possibility that a shop was rented.
"Whether the terrorists hired a shop in the mall is a rumor," Interior Minister Joseph Ole Lenku told CBS News. "We will treat it as such, until the forensic exercise and any other investigation taking place prove it otherwise."
BBC News also reported that corruption played a hand in the siege at the Israeli-owned complex, as fake IDs provided by government officials would have been required to rent the mall shop.
Other details the news network confirmed were that the militants were dropped off outside the mall by two vehicles before the attack and that they used a first-floor ventilation shaft as a hiding place.
Somali Islamist militant group Al Shabaab, which claimed responsibility for the attack and siege that followed, said it targeted the mall because it was home to a number of Jewish and American businesses.
Kenya is now in its third day of official mourning for the victims of the attack.