(AFP) - Seventeen boys were confirmed dead and 70 missing after a fire tore through a primary school dormitory in central Kenya, officials said Friday, leaving distraught relatives desperate for news of their loved ones.

The blaze at the Hillside Endarasha Academy in Nyeri county broke out around midnight, engulfing rooms where more than 150 boys were sleeping.

President William Ruto declared three days of national mourning starting from Monday after what he described as an "unfathomable tragedy".

He said 17 children aged between nine and 13 had lost their lives, vowing to find out how the disaster had happened and hold those responsible accountable.

Deputy President Rigathi Gachagua told reporters at the scene of the disaster that 70 youngsters were still unaccounted for, while 27 were in hospital.

He described the scene as "gory" and said painstaking investigative work using DNA would be required to help identify the victims, also urging relatives and members of the community to help in tracing the missing.

"The bodies recovered at the scene were burnt beyond recognition," national police spokesperson Resila Onyango told AFP.

Tensions were running high among families gathered at the school as they anxiously awaited news.

Many broke down into anguished wailing and tears after officials took them to see the charred bodies in the destroyed dorm.

"Please look for my kid. He can't be dead. I want my child," one woman cried in distress as she left the school.

- 'Panic mode' -

The cause of the inferno was not yet known but Kenya's National Gender and Equality Commission said initial reports indicated the dorm was "overcrowded, in violation of safety standards", and called for an immediate inquiry.

"We parents are in panic mode," said Timothy Kinuthia, who has been hunting for news of his 13-year-old boy.

"We have been here since 5:00 am and we have been told nothing."

AFP footage showed the blackened shell of the dormitory, with its corrugated iron roof completely collapsed.

The destroyed building was sealed off by yellow police tape, with officers stationed at all access points.

The school, which reportedly catered to some 800 children, is located in a semi-rural area around 170 kilometres (100 miles) north of the capital Nairobi.

An AFP journalist saw survivors wrapped in blue blankets against the cold, being loaded into school buses.

Alice Wanjiku said she had come from Nairobi to search for her orphaned nephew.

"We have not heard anything since morning. I will camp here until I find our baby. He is the joy of our family and I hope to find him."

- 'Traumatised' children -

Speaking at the scene, Interior Minister Kithure Kindiki said some of the pupils had ended up in neighbouring homes.

"There are some children who are alive and well, but they are of course traumatised and they are in the hands of those who gave them refuge last night," said Kindiki.

The Kenyan Red Cross said it was on the ground assisting a multi-agency response team and providing psychosocial support.

There have been numerous school fires in Kenya and across East Africa.

In 2016, nine students were killed by a fire at a girls' high school in the sprawling slum neighbourhood of Kibera in Nairobi.

In 2001, 67 pupils were killed in an arson attack on their dormitory at a secondary school Kenya's southern Machakos district.

Two pupils were charged with murder, and the headmaster and deputy of the school were convicted of negligence.

In 1994, 40 school children were burned alive and 47 injured in a fire that tore through a girls' school in Tanzania's Kilimanjaro region.

In 2022, a blaze ravaged a school for the blind in eastern Uganda. Eleven pupils died after they were trapped inside their shared bedroom because the building had been burglar-proofed, government ministers said at the time.

© Agence France-Presse