Kenyan authorities are holding eight people in connection with last Saturday's attack on a Nairobi shopping mall carried out by Somali militants. The four-day siege left 67 people, including civilians and soldiers, dead. Kenyan police interrogated three other people, but they were later released, the interior minister said Friday.
The Somali militant Islamist group Al-Shabab said the attack was "just the premiere of Act 1" and suggested it would be followed by other actions by its "warriors."
Investigators trying to determine the identity of the attackers were making "good progress" in their search through the rubble of the mall where three floors collapsed after a series of blasts and a huge blaze, Interior Minister Joseph Ole Lenku said. Five of the attackers were killed, he said, but survivors of attack have said some may have escaped.
"Police are holding eight suspects as they seek to unmask the face behind the terror attack. Three others were interrogated and released," Ole Lenku said at a news briefing.
Kenyan officials have said they are investigating a theory that the militants may have hired a shop in the mall before the assault to store weaponry, including a heavy machine gun.
Suspects were being held under anti-terrorism laws meaning they could be held "for longer periods before being arraigned in court," Ole Lenku said, although he did not give details.
Meanwhile, three Kenyan newspapers reported on Saturday that a year ago the country's National Intelligence Service (NIS) had warned of the presence of suspected Al-Shabab militants in Nairobi and that they were planning to carry out "suicide attacks" on the Westgate mall and on a church in the city.
In front-page stories, the Nation, Standard and Star newspapers questioned whether the Kenyan government and military may have failed to act on this and more recent warnings this year by local and foreign intelligence services.
"It is not a 'yes' or 'no' answer," Mutea Iringo, principal secretary in the Ministry of Interior, told Reuters. "Every day, we get intelligence and action is taken as per that intelligence and many attacks averted. But the fact that you get the intelligence does not mean something cannot happen.”
"What we are saying is that we are at war, and that every day some young Kenyan is being radicalised by Al-Shabab to kill Kenyans," he added.
Al-Shabab, which is linked to al-Qaeda, said it launched the attack to demand Kenya withdraw its troops from Somalia, where Kenyan forces deployed in 2011 to strike at the group which Kenya blamed for attacks and kidnappings on its territory.
A top Kenyan military official played down reports of a build-up of Kenyan forces near the Somali border, saying that troops who had gathered near Somalia were rotating to join African peacekeepers there and replace other Kenyan soldiers.
Kenyan President Uhuru Kenyatta has said Kenya will not withdraw its force from Somalia.
Meanwhile, Al-Shabab, which taunted Kenya during the mall raid when its militants were still holding out, issued a new threat over social media.
"The mesmeric performance by the #Westgate Warriors was undoubtedly gripping, but despair not folks, that was just the premiere of Act 1," the group said on Twitter, @HSM_PR, a handle it often changes as its accounts are regularly suspended.
Elsewhere in Kenya, a leading Muslim scholar, Ibrahim Lethome, condemned the mall attack when he addressed worshippers at Nairobi's central Jamia mosque Friday. Muslims make up around 10 percent of Kenya's 40 million population, which includes a patchwork of ethnic groups.
"Islam is against the killing of innocent people. Period. It is a crime," he said. But he said the government should avoid persecuting Muslims as it seeks to identify those responsible.
"Sometimes the way the state operates and the government operates creates radicalization," he said.
Al Jazeera and Reuters