The Boston firefighters union, Local 718, endorsed state Rep. Marty Walsh’s mayoral campaign on Thursday night.

The union, which is based at Florian Hall in Dorchester, is headed by Rich Paris.

Other unions that endorsed Walsh earlier this week, according to the campaign, include: Carmen 589, International Longshoremen Association, Roofers Local 33, Sheet Metal Workers Local 17, International Brotherhood of Electrical Workers 2321, Boston Newspaper Printing Pressman, Painters District Council 35, SEIU 509, Ironworkers Local 7, and the Laborers Local 223. Walsh, who was also endorsed by the Greater Boston Labor Council, is a member of Local 223 and a former top official with the building trades’ union.

Walsh, a Dorchester Democrat, is one of 12 candidates for mayor.

The firefighters’ union also endorsed Dan Cullinane for 12th Suffolk state representative. Cullinane is one of three Democrats on the Aug. 13 primary ballot in the special election to fill a vacancy. The primary’s winner will face two independents, Edmond Romulus and Lincoln Larmond, in the September general election.