A union representing 2,000 security officers is moving ahead with plans for a one-day strike as early as Monday that could affect some of the Twin Cities’ biggest corporations, the Star-Tribune reports.

Contract talks broke down on Friday between the union and the seven large contractors that supply security officers to Target, U.S. Bank, Wells Fargo and may other corporate buildings, the article says. The union threatened it would call for a strike if no deal was reached by Sunday, but would not give precise details.