Three people are believed to have died after a trench collapsed on them during construction work on Sandown Road in Sunningdale, Cape Town, the City's fire and rescue service said on Monday. 

Spokesperson Jermaine Carelse said the trench, which was opposite Builders Warehouse, had collapsed shortly after 17:00. 

An added complication was that a water pipe had also burst, flooding the trench. 

"The sand fell on top of them while they were inside the trench," said Carelse. 

Sadly, after working for hours, the team feared the rescue mission would become a recovery mission.  

A fourth person was still unaccounted for, but the construction company is looking into this.

"We have everybody on the scene, including a chaplain," said Carelse of the multi-agency response. 

The rescue operation is expected to continue throughout the night.