Twin Cities-area office janitors kicked off strikes and public protests Monday morning after failing to reach a contract with cleaning companies over the weekend.

"Workers at over 100 buildings across the TC metro ARE ON ULP [unfair labor practice] STRIKE this morning after authorizing strikes last month and no contract reached for 4,000 commercial janitors," SEIU Local 26 wrote on social media.

The demonstrations are part of a "week of action" featuring three days of planned protests, with Service Employees International Union organizers arguing that wages have not kept pace with inflation.

Representatives for the cleaning companies at issue have argued that wages are already competitive and that the union's demands are excessive.

At commercial buildings in downtown Minneapolis, signs read "Fair contract now!" and "Union power." The national SEIU said about 10,000 workers across multiple industries in Minnesota were gearing up for protest action.

"It's a fight for fair wages, safe jobs, and respect," the national SEIU said.

At 11:30 a.m. Monday, workers rallied at the Public Service Building at 505 S. 4th Av. At 5 p.m., they rallied at the Ameriprise Financial Center at 707 2nd Av. S. Demonstrations are planned through Friday, including at the State Capitol in St. Paul and the Minneapolis-St. Paul International Airport, and are focused on stable housing and good schools.

Local officials and workers will also speak out on Monday ahead of a hearing focused on a new labor standards board.

The SEIU said the expired contracts impact more than 5,000 janitors for offices and the airport. Contract negotiations have stretched on for months.