BOGOTA - No bodies belonging to informal miners who were reportedly trapped in a tunnel on Zijin Mining's Colombia concession have been handed over to a rescue team, the government of Antioquia province said on Wednesday.

Road blocks were set up by the community around the mine in Buritica municipality on August 12 to demand a rescue mission, though no official entity has confirmed anyone is missing.

The blockades halted the mine's production. 

Thousands of wildcat miners work in sometimes-deadly conditions in dozens of informal tunnels in Buritica, including many within or adjoining Zijin's concession.

The activities, controlled by the Clan del Golfo crime gang, are a safety issue for the surrounding community and affect Zijin's output, a Reuters investigation last year showed. 

An initial rescue effort on Tuesday to verify whether there were any miners trapped was partially stymied by unidentified people in the tunnel who said they would hand over bodies the next day, according to the provincial government.

The rescue team on Wednesday "had contact with people who are inside the mine. There was not a handover of bodies or cadavers or people presumably trapped in the mine," the head of Antioquia's security department Luis Fernando Suarez said.

The ministry of defense must intervene to lift the road blockades, Suarez said.

"Today we had a meeting with the Minister of Defense during which we presented the complex situation that there is in the municipality," Suarez said. "In our judgment dialogue efforts are exhausted and we have asked the ministry of defense to directly order an intervention."

A spokesperson for Zijin said the company supported the call for an intervention to unblock the roads.

"We need the blockade lifted," they said.

The Ministry of Defense did not immediately respond to a request for comment.

Zijin paid $1-billion in late 2019 to buy the mine from Canada's Continental Gold, despite security concerns related to attacks on staff.