Some security guards at Bedrock LLC-owned buildings in downtown Detroit walked off the job this week because they say their employer, SecurAmerica LLC, is preventing them from unionizing.

The workers voted to strike Monday night, said Aundreana Jones-Poole, representative for Service Employees International Union Local 1, which aims to organize the workers.

According to SecurAmerica, a total of 20 security guards went on strike Monday night and returned to work Wednesday, said Andrea Bitely, senior account executive with Truscott Rossman, which handles public relations for the company.

Atlanta-based SecurAmerica, which was hired by Bedrock in July 2018, employs more than 350 security guards in Detroit.

The union, which has an office in Detroit, would not say Wednesday morning how many security guards went on strike. A message was left with the union Wednesday afternoon seeking an update on its demonstration plans.

Jones-Poole said those protesting work primarily at 1001 Woodward, One Campus Martius and the First National buildings.

"The reason they're on strike is because they've been retaliated against for trying to come together and unionize," Jones-Poole said.

SecurAmerica said in a statement that "only a small number of SecurAmerica officers are participating in the protest" and the company is committed to ensuring there are no lapses in security at the properties.

"...We have provided a fair and respectful working environment for our associates, opportunities for advancement, and a competitive wage and benefit package that includes substantial pay increases for our security officers who are now among the highest paid in Detroit — a minimum of $15 an hour," Ron Hall, vice president of human resources for SecurAmerica, said in a written statement.

In June, the union organized a protest for a $15 minimum wage. SecurAmerica said then that a total of 16 guards went on strike.

Jones-Poole said the contractor initially agreed to the minimum wage hike but is now hiring new employees starting at $12.50. An Oct. 30 job posting for a security officer on the company's website said the wage was "starting $12.50 to $15." The company said through its PR firm that security guards in downtown Detroit start at $15.

For its part, Bedrock wants nothing to do with the dispute. The company said in a statement emailed to Crain's that the efforts of SEIU should be directed toward SecurAmerica, not the Detroit-based real estate company.

"These events are nothing more than a theatrical attempt to explicitly drag us into a labor dispute," the company said in the statement. "To be clear, we have no role in this debate. Leveraging a well-known name for the sake of sensationalized press is disingenuous at best."

The union said it has a meeting scheduled Wednesday with Lt. Gov. Garlin Gilchrist. Politicians including presidential candidates U.S. Sen. Bernie Sanders and U.S. Sen. Kamala Harris expressed support for the workers.