HARTFORD -- The National Labor Relations Board issued a federal complaint Friday against the New Jersey-based company that owns five Connecticut nursing homes -- including the Westport Health Care Center -- where workers are on strike.

The board found that HealthBridge/Care One "failed and refused to bargain in good faith with the union" and made changes to wages, hours and other conditions "without first bargaining with the union to a good-faith impasse."

Those changes prompted about 700 union nurses, nursing assistants, laundry, dietary and housekeeping workers to walk off the job at nursing homes, in addition to Westport, in Danbury, Milford, Newington and Stamford.

According to the 14-page complaint, the NLRB's acting general counsel is seeking an order that requires HealthBridge to reimburse employees lost wages and benefits. A hearing is scheduled for Sept. 10 in Hartford. HealthBridge may dispute the allegations before an administrative law judge.

"The complaint issued by the NLRB today is just the latest evidence of the illegal behavior by HealthBridge designed to line their pockets and marginalize those who care for our state's seniors," said David Pickus, president of the New England Health Care Employees Union, District 1199. He accused the company of denying workers' their right to collectively bargain and imposing conditions "that will push many in our communities further into poverty."

Messages were left seeking comment with a HealthBridge spokeswoman. Earlier this week, spokeswoman Lisa Crutchfield accused the union of striking because it failed to pressure the company into accepting "unrealistic contract proposals any other way."

According to the union, this is the fifth complaint issued by the NLB against HealthBridge and it's the second to refer to "a pattern of bad faith bargaining" in negotiations with the union.

Crutchfield said earlier this week that the company has not been found guilty in court of any violation.