One of the Islamist militants wore a white turban, others black headscarves, witnesses said. Most were dressed in civilian clothes, but a few had donned camouflage fatigues. Some carried sophisticated machine guns, others wielded the AK-47 rifles widely used by African insurgents. Most of the extremists who seized the upscale mall in Nairobi were young and barked orders in English.

By Monday evening, Kenyan security forces said they controlled much of the upscale Westgate Mall, although several militants from al-Shabab, a group allied with al-Qaida, appeared dug in, determined to fight to the death.

With the standoff apparently drawing to a close, there was a growing focus on the identity of the militants and how they could pull off a sophisticated assault that killed at least 62 people and keep security forces at bay for three days. Kenyan Foreign Minister Amina Mohamed said "two or three Americans" and "one Brit" were among the militants in the attack.