Kenya is mourning 148 people killed in Thursday's al-Shabab attack on Garissa university campus, amid questions over why warnings were ignored.
Kenyan newspapers say there was intelligence information of an imminent attack on a school or university.
Locals question why security was not heightened, with only two guards on duty at the time of the attack.
Four more people have been found alive on the campus, but two are suspects and have been arrested, sources say.
One is said to be a Tanzanian national with no known links to the university.
All the bodies have been removed from the scene, Kenya's interior minister Joseph Nkaiserry said. Most of the victims were students, but three police officers and three soldiers were also killed, he added.
Police in neighbouring Uganda say they have received information suggesting a similar attack is being planned there.
Security services appear to have had some information that an attack on an institution of higher learning was in the offing and appear to have warned institutions to be careful, the Daily Nation newspaper reports.
It says the University of Nairobi warned its students on 25 March that it had received intelligence information about a possible attack on a university and asked them to be vigilant.
Locals in Garissa, a city about 150km from the Somali border, also question why security was not boosted in light of the intelligence.
"It's because of laxity by the government that these things are happening. For something like this to happen when there are those rumours is unacceptable," said Mohamed Salat, 47, a Somali Kenyan businessman.
One of the survivors, who hid in bushes during the assault, said the students had raised security issues late last year, but only two armed guards had been provided. Another said the gunmen appeared to know the site well.
One witness told the BBC she heard the gunman receiving instructions on mobile phones, and speaking in Swahili, an official language in Kenya - raising the possibility the attackers were locals and not from Somalia, al-Shabab's heartland.
A dusk to dawn curfew has now been imposed in Garissa and three nearby counties.
In his address to the nation after the attack, President Uhuru Kenyatta said he had instructed the police chief to speed up the training of 10,000 recruits, because Kenya had "suffered unnecessarily due to shortage of security personnel".
Al-Shabab was also blamed for the Westgate Mall massacre in Nairobi in 2013 in which 67 people died.
President Barack Obama has expressed his condolences, saying "words cannot adequately condemn" what had happened.
The UN too expressed its outrage, paying tribute to Kenya's role in the African Union's mission in neighbouring Somalia against al-Shabab.
The bodies of those killed in Garissa have been flown to the capital Nairobi for identification, as the local mortuaries have been unable to cope, and many of the students killed came from other parts of the country.
The masked attackers killed two security guards at dawn on Thursday, then rampaged through campus, shooting and shouting "we are al-Shabab".
They singled out Christians and shot them, witnesses said.
At the scene: Wanyama wa Chebusiri, BBC Africa, Garissa:
A second-year student who hid for 10 hours in a wardrobe is one of about 500 survivors still being held at a military facility, where they are undergoing counselling.
Her father drove for four hours from Nairobi when he was unable to get hold of her during the siege.
He told the BBC about his desperate search for his daughter at the mortuary, hospital and military airstrip.
Late in the afternoon, when he had almost given up hope, he got a text: "Dad call me". They have yet to be reunited but his relief is palpable.