(CNN) -- Boston Fire Chief Steve Abraira, whose deputy chiefs criticized him over his handling of the Boston Marathon bombings, has submitted his resignation, the Boston Fire Department said Monday on its official Twitter account.
Abraira's resignation is effective Friday.
In an April 26 letter to Boston Mayor Thomas Menino, 13 deputy fire chiefs said they had no confidence in Abraira, asserting that he failed to assume command responsibility or show any leadership at the scene.
"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 read.
CNN obtained the letter from a deputy chief who signed it but requested anonymity.
In the letter, the deputies describe an e-mail that Abraira sent to all department members, saying that when he arrived at the scene, "it was clear that our Command Officer had the incident well in hand and that our department was fully active in a support role with our law enforcement partners."
The deputies call Abraira's argument "illogical" and "mere rationalization to justify his behavior," saying that when Abraira arrived, the Boston Fire Department was "still heavily involved in the incident" because of the possibility of "second explosions," "additional suspicious packages" and "structural stability concern of buildings," among other issues.
But Abraira defended his actions to CNN.
"In their estimation, they believe that if you don't assume command, you don't have responsibility there for what goes on," he said. "I tried to explain to them, if I'm on the scene, I'm still responsible. That's it. But they don't believe it."
The chief told The Boston Globe that he was comfortable with the way his commanders were handling the incident.
"The nationally accepted practice is that you only take command (as chief) 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," he told the paper.
Two bombs exploded at the finish line of the marathon on April 15, killing 3 and injuring more than 260 others.
One of two bombing suspects, Tamerlan Tsarnaev, died after a gunfight with authorities four days later. After much secrecy and protest, he was buried in a rural Virginia cemetery.
Police took his brother, Dzhokhar Tsarnaev, into custody on April 19 after finding him hiding in a boat in the backyard of a Watertown, Massachusetts, home.
He has been charged with using a weapon of mass destruction and malicious destruction of property causing death and is in federal custody.
CNN's Ed Payne contributed to this report.