Trash pickup Tuesday in parts of Montgomery County may be disrupted by a strike for the second time in a month, as workers trying to organize a union at a Laurel hauling company went off the job to protest the firing of an employee.

Unity Disposal and Recycling is one of the three firms that hold contracts with Montgomery for residential trash pickup. The company is also a contractor for Howard County. The strike may disrupt or delay pickup in parts of Bethesda, Chevy Chase, Wheaton and Columbia.

Nicole Duarte, a spokeswoman for the Laborers International Union of North America, said in a statement that a worker was fired Monday after a “captive audience meeting” called by company officials on Friday to discourage formation of a union. Duarte said the worker was let go for speaking out at the meeting.

Unity chief executive Cordell Proctor did not return a phone message Tuesday morning.

Newly unionized workers at the Gaithersburg-based Potomac Disposal struck for three days over labor problems last month. The predominantly Latino drivers and helpers accused the company of threatening immigration enforcement against them in an attempt to leverage stalled contract talks.