Johannesburg - Rescue helicopters were looking for survivors after a boat carrying 20 people reportedly sank off South Africa's eastern coast, reported the SAPA news agency Monday, citing television reports.

According to SAPA, National Sea Rescue Institute spokesman Craig Lambinon said one crew member managed to swim to safety after the boat sank near Oyster Bay in the Eastern Cape region.

Rough sea conditions and gale force winds were making search and rescue operations difficult. Lambinon said an overturned life raft had been spotted. (dpa)