State Department spokeswoman Victoria Nuland said the department had accepted the resignations of four people: Boswell as well as two others in the bureau of diplomatic security and one in the bureau of Near East Affairs. She would not name the other three officials.
Some of those who resigned may have the option of being reassigned to other duties, the officials said.
The department declined immediate comment on the resignation of the officials whose decisions had been criticised in the unclassified version of the Accountability Review Board's report that was released yesterday.
The report singled out the Bureau of Diplomatic Security and the Bureau of Near East Affairs for criticism. It said there was a lack of co-operation and confusion over protection at the mission in Benghazi.
The board's co-chairman, retired Admiral Mike Mullen, told reporters that the board had not determined that any officials had "engaged in wilful misconduct or knowingly ignored his or her responsibilities".
But Mullen, a former Joint Chiefs of Staff chairman, added, "We did conclude that certain State Department bureau level senior officials in critical levels of authority and responsibility in Washington demonstrated a lack of leadership and management ability appropriate for senior ranks in their responses to security concerns posed by the special mission."
Mullen said the mission's security fell through bureaucratic cracks caused in part because buildings were categorised as temporary. The report said that budget constraints had caused some officials to be more concerned with saving scarce money than in security.
Co-chairman Thomas Pickering, a retired ambassador, said the personnel on the ground in Benghazi had reacted to the attack with bravery and professionalism. But, he said, the security precautions were grossly inadequate and the contingent was overwhelmed by the heavily armed militants.
"They did the best they possibly could with what they had but what they had wasn't enough," Pickering said.
Members of Congress emerged from briefing sessions with harsh words for the State Department.
Democratic Congressman Adam Schiff, a member of the House intelligence committee, said security was "plainly inadequate, intelligence collection needs to be improved, and our reliance on local militias was sorely misplaced".
The House intelligence committee chairman, Republican Mike Rogers, said the report laid bare "the massive failure of the State Department at all levels, including senior leadership, to take action to protect our government employees abroad", and complained that no one was being held accountable.
Rogers also said he was dissatisfied with the lack of progress in finding the attackers.
Secretary of State Hillary Clinton said the department had begun to put in place some of the report's recommendations to improve security, including increasing by several hundred the number of Marine guards at diplomatic missions.
- AP