CHICAGO — Ten days after walking off their jobs, immigrant workers at Cygnus Corp.’s soap factory here scored a victory by being hired back without reprisals and with an increase in pay.

An executive from Cygnus’ parent company flew in, fired the director of human resources and authorized a pay increase without firing any of the workers who participated in the strike.

The strike began on July 30, when Cygnus told workers with unclear immigration status that they would be fired if their status was not resolved by Aug. 10.

The threat of immigration reprisals based on “no match” Social Security numbers was made after workers had complained to management about low wages.

Wages started at $6.50 per hour until recently, when the minimum wage was increased to $7.50 per hour. Prevailing wages for bottling and packaging liquid detergents and soaps, however, are $8.50 per hour.

Workers at the plant, almost all Mexican immigrants, are divided by Cygnus as either temporary or full-time. All workers, whatever their designation, were making the same pay, with no benefits.

Some of the “temporary” workers have been there as long as 11 years.

The workers decided to strike even though they have no union representation.

Shortly after the strike began, representatives of International Association of Machinists (IAM) District 8 visited the picket lines and, within days, the workers had categorically voted to have the IAM become their union.

Cygnus, which is based in Riverdale, Ill., is owned by Marietta Corp., which is in turn controlled by Ares Management, a $16 billion multinational private equity firm that also owns the Samsonite luggage company, the Maidenform lingerie brand, the Serta mattress manufacturer, and the House of Blues music venue chain.

To counteract the strike, Cygnus hired replacement workers from a temporary staffing agency that primarily employs African Americans, in a brazen attempt to divide the workers along racial lines.