The leader of a Kenyan cult who allegedly encouraged over 400 followers to starve themselves to death has pleaded not guilty to manslaughter, in one of the worst ever cases of cult-related mass deaths.

Self-proclaimed pastor Paul Mackenzie appeared in court in the coastal city of Mombasa alongside 94 other suspects on Monday.

Mr Mackenzie was arrested last April after 429 bodies, including children, were dug up from mass graves in Shakahola, a remote forest about two hours' drive west of the town of Malindi. Most of the bodies showed signs of starvation and assault.

"There has never been a manslaughter case like this in Kenya," prosecutor Alexander Jami Yamina told AFP.

The prosecution say over 400 witnesses will testify over the next four days.

Mr Yamina said the case was unique in Kenya, and the suspects would be prosecuted under a law relating to suicide pacts.

When the case broke last year Kenyans were shocked and horrified that people could willingly starve themselves to death. It became known as the "Shakahola Forest Massacre".

Mr Mackenzie allegedly told his followers they would get to heaven more quickly if they stopped eating.

Mr Mackenzie is also facing two other trials: one for terrorism which started in July and another on child abuse charges, which includes subjecting children to torture, assault, cruelty to children and infringing a child's right to education - which he denies.

Survivors say children were supposed to be the first to starve themselves, according to a macabre order drawn up by Mr Mackenzie. Then the unmarried, women, men, and last of all, church leaders.

Mr Mackenzie set up his Good News International Church in 2003, but said he closed it in 2019.

He encouraged his followers to move to Shakahola forest and prepare for the end of the world to "meet Jesus".

Pastor Mackenzie is reported to have owned 800 acres of the remote forest, where there is no mobile network.

The forest was partitioned into different areas and given biblical place names, such as Judea, Bethlehem and Nazareth.

In March this year, the authorities released some victims' bodies to relatives after months of identifying them through DNA tests. So far 34 bodies have been returned.

Mr Mackenzie preached that formal education was satanic and used to extort money.

In 2017 and again in 2018, he was arrested for encouraging children not to go to school as he claimed education was "not recognised in the Bible".

He also allegedly encouraged mothers to avoid seeking medical attention during childbirth and not to vaccinate their children.

Mr Mackenzie was convicted last November of illegally operating a film studio associated with his preaching and distributing films without a valid filming licence and sentenced to a year in prison.

Kenya is a profoundly religious country with 85% of the population identifying as Christian. There have been previous cases of people being lured into dangerous, unregulated churches or cults.