LOS ANGELES – A union representing employees at two Hyatt hotels announced today that workers have voted to authorize a strike.

This past Thursday, employees at the Hyatt Regency Century Plaza and the Hyatt Andaz voted to strike, if necessary, said Leigh Shelton of UNITE HERE Local 11.

Shelton said the vote “represents a major escalation of a labor dispute with the Hyatt Corporation, which has become the target of labor demonstrations across North America in recent weeks.”

Hyatt workers and about 4,000 other hotel workers in Los Angeles have been without a contract since November 2009, Shelton said.

Thirteen people were arrested in Century City on Thursday during a march and rally in support of recently laid off janitors, police said. About 300 people attended the march and rally outside the Century Plaza office building where the janitors used to work. The protest was organized by SEIU United Service Workers West.