Seven people died instantly when lightning struck the house in which they stayed at Goqwana village, Tsolo, in the Transkei, Eastern Cape police said on Monday.
Superintendent Nondumiso Jafta said five others were taken to the St Lucy hospital with injuries.
All the victims were in one room at the house when the lightning struck on Sunday. Their names would be released once their families were informed, Jafta said.
She said the weather in the area was bad, with lots of lightning.
Another two men died after being struck by lightning at Cradock on Saturday afternoon, police spokesperson Captain Erris Claassen said.
He said Toekie Falman (32) and Booi Adam (30) were waiting for a lift when rain started pouring at about 2.30pm on Saturday.
A few minutes later, lightning struck a tree near to where the two men were waiting. Another strike then killed Falman and Adam, he said.
Five other people were taken to a local hospital after they were injured, and were discharged after receiving treatment, said Claassen.
He said Booi and Falman were sheltering under the tree during the rainstorm. — Sapa