Uganda is heightening security and has commenced a massive search after m Militants linked to the Islamic State group massacred at least 41 people, mostly students, in western parts of the country near the border with the Democratic Republic of Congo.
The country’s first lady Janet Museveni while updating on the current situation on Saturday evening said the government was still investigating the whole incident.
"The government through the security agencies is trying to follow up on what actually happened. And it is on the top of the situation, we believe that justice will prevail," said Janet Museveni, Ugandan minister of Education and Sports and first lady.
Officials and witnesses said guns and knives were used in a grisly late-night assault, and dormitories were set ablaze at Lhubiriha Secondary School in Mpondwe.
Some students recounted the incident, terming it horrific.
"We hadn't yet fallen asleep when we heard people arriving and saying: open up, open up! We didn't reply. Then they started shooting at the windows and the door. We went to hide under our beds on the floor. As they continued to shoot at the windows, one of us was hit by a bullet and started shouting: "Help, come and help me! When they couldn't open the door, they continued to shoot at the windows, then set fire to our dormitory while we were inside. They then moved on to the girls' dormitory," said Mumbere Edgar Dido, a student who survived the attack.
The military said it was pursuing the attackers from the Allied Democratic Forces (ADF), who also abducted six people during a raid on a school late Friday before fleeing back towards the Democratic Republic of Congo.
UN Secretary-General António Guterres "strongly condemns" the attack, and sent his "heartfelt condolences" to the families of the victims, his spokesman said Saturday.
"Those responsible for this appalling act must be brought to justice," Guterres' spokesman Farhan Haq said in a statement.
"Appalled by the attack at a secondary school in Western Uganda," wrote Molly Phee, the US Assistant Secretary of State for African Affairs, on Twitter.
"We send our condolences to the affected families and condemn the attack on schoolchildren."
France also condemned the deadly attack "in the strongest possible terms," a foreign ministry spokeswoman in Paris said Saturday.
Uganda Peoples' Defence Forces (UPDF) spokesman Felix Kulayigye said the six kidnapped were taken towards Virunga National Park, a vast expanse that straddles the border.
"UPDF embarked on pursuing the perpetrators to rescue the abducted students."
Police have not released details about the victims' ages or how many were students.
Outside the school, heavily armed soldiers and police stood guard, as a large crowd gathered and distraught survivors were comforted by loved ones.
It is the deadliest attack in Uganda since twin bombings in Kampala in 2010 killed 76 in a strike claimed by the Somalia-based Al-Shabaab group.
According to a police report seen by AFP, police and military units were alerted to a "big attack" at the school around 11:00 pm (2000 GMT) on Friday evening.
"On arrival, the school was found burning and the dead bodies of students were found lying in the compound and the school's food store was broken into" with items missing, the report stated.
The school is less than two kilometers (1.2 miles) from the border of DR Congo, where the ADF is mainly active. It has been accused of killing thousands of civilians there since the 1990s.
Major General Dick Olum told AFP that intelligence suggested the presence of the ADF in the area at least two days before the attack, and an investigation would be needed to establish what went wrong.
The attackers appeared to have detailed information about the school, he added.
"They knew where the boys and girls' dormitories resided," said Olum from Mpondwe, who has been leading an army operation against the ADF in Uganda and the DR Congo.
"This is why the rebels locked the boys' dormitory and set it on fire. The rebels did not lock the girls' section and the girls managed to get out, but they were cut with machetes as they ran for safety, and others shot."