JOHANNESBURG - More than 200 illegal miners were trapped underground in an abandoned mine near Johannesburg, authorities said on Sunday.

"Approximately 30 people are trapped towards the top of the old shaft and the rest down a steep tunnel," said Werner Vermaak, spokesman of emergency agency ER24.

Rescue workers were at the scene, searching for the miners. So far no deaths were reported.

Vermaak said rescue workers were able to speak to the miners trapped near the top. The miners told rescuers that no one was injured.

However, the conditions underground were unknown, Vermaak said.

Water was lowered down to the miners who are believed to be about five meters underground.

The miners were trapped after allegedly being robbed of their gold on Saturday afternoon at the Gold One shaft in Benoni outside Johannesburg.

It seems the mine was abandoned a long time ago and is now being used by illegal miners.

The rescue effort will likely take several hours.

The incident highlighted the growing concern about illegal mining in the country. In March 2012, at least 20 illegal miners were buried alive after a rockfall hit a closed gold mine in the eastern South African province of Gauteng.