JOHANNESBURG (AP) — At least nine people have died while eight others are still missing in South Africa after they were swept away by a flash flood along the Jukskei river in Johannesburg, rescue officials said Sunday.

Two bodies were recovered on Saturday and a further seven bodies were found when the rescue mission was resumed on Sunday morning.

The dead and missing were all part of a congregation conducting religious rituals along the river on Saturday, according to officials.

Rescue teams are conducting interviews with some of the people who survived or were rescued to establish exactly how many people are accounted-for.

Johannesburg Emergency Services spokesman Robert Mulaudzi said Sunday that officials continually warn residents about the dangers of conducting the rituals along the river.

“We have been receiving a lot of rain on the city of Johannesburg in the last three months and most of the river streams are now full. Our residents, especially congregants who normally practice these kinds of rituals, will be tempted to go to these river streams," he told a news briefing.

“Our message for them is to exercise caution as and when they conduct these rituals,” added Mulaudzi.

Congregations often gather to conduct church rituals including cleansing and baptism along the Jukskei river which runs along many townships including Alexandra in the east of Johannesburg.