• Editor&39;s note: This is a developing story. We will bring you updates as more information becomes available.

JOHANNESBURG - At least 90 mine workers who are members of the Association of Mineworkers and Construction Union (Amcu) were trapped underground at mine in Barberton in Mpumalanga on Friday, the union said.

Union official Manzini Zungu said at least 80 miners had been brought to the surface.

“At this point it’s unclear what caused the disaster, but further information about the horrific incident will be made available during the course of the day. We are on our way to the mine as we speak,” Zungu said.

The mine reportedly caved in at around 8.40am on Friday. According to Zungu no fatalities were reported.

Details on the incident were sketchy as the exact number of those trapped could not be confirmed.

ER24 had earlier reported that 49 miners had been brought to the surface having sustained minor injuries.

The Barberton Times newspaper reported that between 60 to 70 miners had been taken to the Barberton Hospital for treatment and observation.

The newspaper further reported that contact had been made with the miners who are trapped below surface.

See more photos of ambulances meeting to decide on plan of action: https://t.co/bOdRVxhYKG pic.twitter.com/oFvKd2Ahfj — Lowveld Media (@LowveldMedia) February 5, 2016

LilyMine People gathered at the gate of the mine. Photo via @LowveldMedia pic.twitter.com/BSyMOYiC4P — Sun du Toit (@SuneDT) February 5, 2016

LilyMine Mpumalanga EMS says paramedics and mine rescue services are on scene. Pic via Lowveld media. pic.twitter.com/nzG4i80MOO — Jacaranda News (@JacaNews) February 5, 2016

* For more on this story, watch the video in the gallery above.