BOGOTA - Road blockades set up by community members remained around Zijin Mining's Colombia concession on Thursday, after nearly a week of protests which have hit the Chinese company's production.

The blockades were set up around the gold mine in Buritica municipality on August 12 to demand a rescue mission to find informal miners allegedly trapped in a tunnel. It was not clear how many miners were presumed to be trapped or killed or what incident may have occurred in the tunnel. 

Production was stopped because of the blockades, the company said earlier this week, though a Zijin spokesperson did not respond when asked on Thursday whether output remained halted.

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 any miners were 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.

No bodies were handed over on Wednesday, nor on Thursday.

"Unfortunately there has not been a hand-over of bodies presumably inside the mine," the head of Antioquia's security department Luis Fernando Suarez said in a Thursday video posted on social media.

The provincial government insists the blockades be lifted, he said, adding, without further details, that unidentified people had obliged Buritica shopkeepers to close their businesses.

Antioquia has called on the defense minister to intervene, but the national government has not spoken publicly about the request.

A Buritica resident told Reuters roads were open intermittently on Thursday.

Local mayor Luis Hernando Graciano has told local media two people are missing in the mine and that there are "many interests" connected to illegal mining in the area.

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