Kenya Wildlife Service Spokesman Paul Udoto said the seven members of a church youth group from Nairobi were on a nature walk at the gorge when the incident happened.
“One body has been retrieved while search efforts to account for the missing six are ongoing despite the darkness in the gorges,” he said.
The seven went missing just before dusk when the 40-member youth group from Mukara PCEA church in Nairobi encountered sudden flash floods.
“The rains resulting in the unexpected flash floods had fallen elsewhere and not in Hells Gate and its environs,” said Udoto.
Guides accompanying the youth group managed to rescue the rest of the party to safety.
“Police are helping with the ongoing search efforts,” said Udoto.
Hell’s Gate National Park lies to the south of Lake Naivasha.