City of Boston Steve Abraira, the Boston Fire Department's first Latino chief, was also the first to be appointed from outside the department's ranks.

Boston Fire Chief Steve Abraira resigned Monday after 13 deputy chiefs accused him of mishandling the Boston Marathon bombings.

In a letter to Mayor Thomas Menino and Fire Commissioner Roderick Fraser, Abraira — the fire department's first Latino chief and its first to have been hired from outside its union — blamed a "vocal and aggressive minority" for consistently resisting his efforts to reform the department since he was appointed in 2011.

The final straw was a letter of no confidence that the deputies — all of whom came up through the ranks and are members of the union — sent to Menino on April 26, which complained that Abraira ceded control of the investigation of the marathon bombings to federal authorities.

"At a time when the City of Boston needed every first responder to take decisive action, Chief Abraira failed to get involved in operational decision-making or show any leadership," the letter said.

The City Council had scheduled a meeting later this month to discuss the letter, which called Abraira a "ghost fire chief" who regularly stepped back from fire scenes to "shield himself from immediate accountability while setting the stage for under­mining the confidence and authority of his command staff."

Abraira's letter Monday said Fraser's "selection of me as Chief never had the support of a number of members of the Department who preferred that the Chief be selected from within the ranks of the Department itself."

Fraser's and Menino's offices, which have stoutly defended Abraira, referred calls for comment to the fire department, which said in a two-sentence statement that Fraser had appointed Deputy Chief John Hasson — a 40-year veteran of the department who signed the letter of no confidence — as acting chief.

"We thank the chief for his service to the people of Boston," a spokesman said.

Speaking separately to the Boston Herald, Fraser said: "I like Chief Abraira and am sorry to see him go. I wish him luck in whatever his next chapter may be."

Communicating mainly through public letters, Abraira and his deputies have fought a bitter feud since the Boston Marathon bombings, which killed three people and injured 264 others on April 15.

"At a time when the City of Boston needed every first responder to take decisive action, Chief Abraira failed to get involved in operational decision-making or show any leadership," the deputies' letter, which was first reported by the Herald. "You can unequivocally consider this letter a vote of no confidence in Chief Abraira."

(The Herald's original story is available here behind a paid firewall.)

Abraira told The Boston Globe last month that he had acted appropriately, saying his command staff had control of the scene.

"When I got there, I was comfortable with what was going on," he said. "The nationally accepted practice is that you only take command if there's something going wrong or if you can strengthen the command position or if it's overwhelming for the incident commander, and none of those things were in fact happening."

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Abraira's attorney responded more sharply, threatening to sue the deputies in a letter he sent them last month.

"Your conduct is nothing more than a transparent effort to hide the inadequacies of your own performance and to interfere with my client's efforts to improve the Boston Fire Department," that letter said.

Noting that the deputies acted just 11 days after the bombing, Abraira's attorney called their revolt "a misplaced and frankly outrageous attack intended to strengthen your ability to reject and obstruct Chief Abraira's efforts to bring the BFD in line with modern fire fighting practices."

Abraira's resignation will take effect Friday.

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