Medford Mayor Breanna Lungo-Koehn has promoted a deputy fire chief to fill in as the department’s interim chief, ending a two-week stretch in which firefighters were without a top leader.

Deputy Chief Todd Evans has been selected to serve as provisional fire chief, Lungo-Koehn wrote in a letter to the City Council Thursday morning. The swearing-in will be taking place later today, she said.

The fire department had been operating without a chief since John Freedman retired on Feb. 21 after nearly 30 years of service, serving as the department’s leader in the final two.

“I’m extremely hopeful that Chief Evans will move the department in the right direction,” Lungo-Koehn wrote in her letter. “He is committed and dedicated to doing the work.”

Controversy has surrounded the department since a wave of sick calls in early February cost the city nearly $100,000, a situation the mayor believes “forced” Freedman to retire.

The fire union on Feb. 20 filed an unfair labor practice complaint against Lungo-Koehn with the state Department of Labor Relations, alleging the mayor “defamed” the union on the city’s website and in the media, amongst other charges.

An attorney for the Medford fire union accused Lungo-Koehn of breaking the law by initially offering a firefighter from outside the city to serve as interim chief. The department follows civil service law which requires promotions be made internally only.

The Professional Fire Fighters of Massachusetts sent a letter at the time of Freedman’s retirement to local unions, “imploring members from outside departments to refrain from applying for Interim Fire Chief and Fire Chief positions” in Medford.

“As you all know we contracted with an interim outside of the department who was (supposed) to start Feb. 26th, but he was dissuaded,” Lungo-Koehn wrote in her letter.

Promoting a firefighter to the chief’s position in the interim was complicated in Medford as the department “doesn’t have a civil service eligible list,” the mayor told the Herald late last month.

Two years ago, four deputies signed up to take the required chief’s exam, but only Freedman ended up taking it, meaning he was the “only option” for the hire, the mayor said.

Taking a chief’s exam is required in order to be on the civil service eligible list for the position.

When there is no such list, the “hiring department” could fill a vacancy on a “provisional basis” by appointing someone from within or outside the department, according to the state Civil Service Commission.

Lungo-Koehn told the Herald on Wednesday that the city is “not close” to hiring a permanent chief.

In a statement to the Herald on Wednesday, union President Walter “Eddy” Buckley said members were pleased the mayor “finally started looking internally within our department for candidates for Chief.” But he accused her of not following the law by not appointing the “most senior deputy chief.”

A city ordinance highlights that in a chief’s absence, the senior deputy chief would take on leadership. But Lungo-Koehn has argued the city charter gives her “full authority to appoint all department heads,”

“The Union cannot allow her to do as she pleases because she doesn’t agree with the law regardless of if that candidate is internal or external,” Buckley said.

Before Evans’ appointment as provisional chief, the State Fire Marshal’s Office delegated authority of the department to Lungo-Koehn last week, a procedural move that prompted backlash from the union and critics on social media.

“Under state law, the State Fire Marshal has authority over certain fire safety permitting and inspection functions,” an office spokesperson told the Herald Wednesday. “Delegating that authority to local officials is the standard administrative process to ensure that these functions continue uninterrupted.”