Top Kenyan officials were warned of Nairobi mall attack

An intelligence report saying Kenya's security agencies were alerted to a possible attack on a Nairobi mall has the government facing questions over whether it ignored warnings about last week's assault, the country's media outlets revealed.

According to the leaked report, which was obtained by Al Jazeera, Kenyan officials were warned last September that Al-Shabab was planning suicide attacks on the Westgate mall and the Holy Family Basilica, a church in Nairobi. In January an intelligence briefing looked at the possibility of attackers' storming a building and holding hostages, as happened last week.

The report's conclusion is quite damaging to the Kenyan government because it lists recipients of the intelligence document, including top cabinet officials, according to Al Jazeera's Nazanine Moshiri, reporting from Nairobi.

The leaked report raises questions about why security was not increased at the Westgate mall. The briefing adds to other credible reports that the attackers were able to rent areas in the mall to store weapons in preparation for the attack.

Critics also question the Kenyan government's current investigation, which has failed to account for dozens of people still reported missing.

Earlier this month, the Israeli embassy in Nairobi raised concerns about a possible attack on its citizens. The embassy also revealed that a number of Somalia-based Al-Shabab fighters were apparently given refugee cards to enter Kenya.

Armed members of Al-Shabab, a Somali militant organization, attacked the upscale Westgate mall on Sept. 21, killing 68 people and injuring 175. In an audio message posted on an Al-Shabab-linked website Wednesday night, Ahmed Godane, also known as Mukhtar Abu al-Zubayr, said the mall attack was in retaliation for Kenya's October 2011 incursion into southern Somalia in an attempt to eliminate insurgents.

"Take your troops out or prepare for a long-lasting war, blood, destruction and evacuation," Godane said in the message, apparently directed at Kenya’s government.

Al-Shabab, which formally merged with al-Qaeda in 2012, once held parts of the Somali capital, Mogadishu, but has been on the decline since the 2011 Linda Nchi invasion thwarted an attempted takeover of the deteriorating Somali state.

The group is perhaps most widely known for the twin bombings in Uganda that killed 74 people during the 2010 World Cup. That attack was the first major Al-Shabab strike outside Somalia.

Analysts say the Westgate attack was surprisingly sophisticated, given the group's apparent decay over the past couple of years, and indicates that Al-Shabab is still capable of inflicting large-scale casualties in nearby countries.

With Al Jazeera and wire services