Al-Shabaab, a terrorist group based in Somalia that has ties to al-Qaida, laid siege to the upscale Westgate shopping center in Nairobi, Kenya, Sept. 21. The attack left more than 60 people dead.
A report from a joint Kenyan committee on national security and defense found security agencies twice failed to take action despite warnings of an imminent attack.
"There was general information on the impending terror attack on all the malls and other strategic Western interests, especially in Nairobi," a section of the report published Sunday by the Daily Nation newspaper in Kenya said. "The information was made available to the relevant security officers in Nairobi County on Aug. 6, 2013, and on Sept. 2, 2013."
The report said about a dozen men carried out the attack and four were killed during the security response.
Kenyan President Uhuru Kenyatta, elected last year, was excused from part of his war crimes trial at The Hague, Netherlands, so he could deal with the aftermath of the attack. He's wanted on charges of committing crimes against humanity during post-election violence in 2007-08.