Reuters could not immediately reach the union for comment.
The dispute is linked to negotiations over worker productivity bonuses and profit-sharing entitlements, Orla said in a statement, adding that the work stoppage did not follow procedures under Mexican law, including the filing of a strike notice.
Orla said it is in talks with union leadership to safely resume operations and return employees to work as soon as possible.
The Canadian miner said all the equipment required to maintain the safety of the operation and the environment continued to be operated and monitored.
The company and union representatives are scheduled to meet with the Department of Federal Labour Conciliation on Tuesday, June 2.
"Given the current duration of the production interruption and the nature of heap leach processing, the Company will assess any potential impact of the work stoppage on its full-year production guidance for Camino Rojo," Orla added.
Heap leaching is a mining method where a chemical solution is dripped over piles of crushed ore to dissolve and extract precious metals like gold. The mine produced 96,764 ounces in 2025.
Earlier in May, Equinox Gold (EQX.TO) said it would acquire Orla Mining in an all-stock deal to create a North American gold producer worth about $18.5 billion.
