Attorney General Martha Coakley’s office has filed a housing discrimination lawsuit against the owner of an apartment building in the Port Norfolk neighborhood.

According to the lawsuit filed in Suffolk Superior Court, Shirley Smith Bragel allegedly told a potential tenant that she could not rent an apartment at 12 Lorenzo St. because the potential tenant received a Section 8 federal housing subsidy. The potential tenant is a single mother, who lost her Dorchester home last year and has a 21-year-old daughter and a four-year-old son, according to court documents.

Included in the lawsuit were Bragel Associates, the Bridgeview Realty Trust and George and Shirley Smith Bragel. The Bragels, Quincy residents who own several properties in Boston and office space on Dorchester Ave., could not be reached for comment on Monday.

The Lorenzo St. property was the center of controversy last year as well. Members of Port Norfolk’s civic association in late September objected to the operation of a sober home – a residential drug and alcohol recovery program – out of the three-unit property because they were not notified beforehand. Weeks later, the operator of the sober home, Carl Smith, was indicted by Coakley for participating in a fraudulent drug-screening operation. He pleaded not guilty.

The allegation of housing discrimination against the Bragels first arose in a complaint filed with the Massachusetts Commission Against Discrimination in May 2011. The commission found “probable cause” in September 2011, according to court documents on file in Suffolk Superior Court.

Coakley's lawsuit states that Shirley Bragel told the alleged victim’s real estate agent that she did not want “those type of people” renting the Lorenzo St. apartments. “Ms. Bragel stated that if she rented to one Section 8 tenant, then she would have to rent all the units to Section 8 tenants,” the lawsuit says.

When Bragel repeated the statement to the potential tenant, the tenant started to cry, according to the lawsuit.

The attorney general’s office in the lawsuit asks for damages, up to $5,000 for each violation of housing and consumer protection laws, and requirements for the Bragels to attend training sessions on the state’s fair housing law.

“Realtors, brokers and landlords in Massachusetts must understand that discrimination against those holding housing assistance subsidies is illegal and we will seek to hold accountable those who break the law,” Coakley said in a statement.