WASHINGTON — Ending one of the longest, costliest, and most bitterly partisan congressional investigations in history, the House Select Committee on Benghazi issued its final report Tuesday, finding no new evidence of culpability or wrongdoing by Hillary Clinton in the 2012 attacks in Libya that left four Americans dead.

The 800-page report, however, included some new details about the night of the attacks, and the context in which they occurred, and it delivered a broad rebuke of government agencies like the Defense Department, the Central Intelligence Agency, and the State Department — and the officials who led them — for failing to grasp the acute security risks in Benghazi, and especially for maintaining outposts that they could not protect.

The committee, led by Representative Trey Gowdy, Republican of South Carolina, also harshly criticized an internal State Department investigation that it said had allowed officials like Clinton, then the secretary of state, to effectively choose who would investigate their actions.

In addition, it reiterated Republicans’ complaints that the Obama administration had sought to thwart the investigation by withholding witnesses and evidence.

The report, which includes perhaps the most exhaustive chronology to date of the attacks on a US diplomatic compound and their aftermath, did not dispute that US military forces stationed in Europe could not have reached Benghazi in time to rescue the personnel who died — a central finding of previous inquiries.

Still, it issued stinging criticism of the overall delay in response and the lack of preparedness on the part of the government.

“The assets ultimately deployed by the Defense Department in response to the Benghazi attacks were not positioned to arrive before the final lethal attack,’’ the committee wrote. “The fact that this is true does not mitigate the question of why the world’s most powerful military was not positioned to respond.’’

But the lack of any clear-cut finding of professional misconduct or dereliction of duty was certain to fuel further criticism of the length the investigation — more than two years — and the expense, estimated at more than $7 million, in addition to Democrats’ allegations that the inquiry was specifically intended to damage Clinton’s presidential prospects.

After a campaign stop in Denver on Tuesday, Clinton told reporters the investigation had uncovered nothing to contradict past findings, arguing that the House committee’s work had assumed a “partisan tinge.’’

“I’ll leave it to others to characterize this report,’’ she said, after taking a rare question from the traveling news media, “but I think it’s pretty clear, it’s time to move on.’’

In a sign that Gowdy was also facing pressure from the right, two of the committee’s conservative members, Jim Jordan of Ohio and Mike Pompeo of Kansas, wrote a 48-page addendum including somewhat harsher criticism of the Obama administration, its response to the attacks, and its subsequent public explanations.

“Officials at the State Department, including Secretary Clinton, learned almost in real time that the attack in Benghazi was a terrorist attack,’’ Jordan and Pompeo wrote. “With the presidential election just 56 days away, rather than tell the American people the truth and increase the risk of losing an election, the administration told one story privately and a different story publicly.’’

Technically, the report is not final until the full committee votes to accept it, which is expected as early as July 8. Still, some changes are possible, if they are accepted and approved by a majority vote.

By far, the committee’s most significant disclosure, even by Republicans’ own account, was unintentional and not directly related to Benghazi: that Clinton had exclusively used a private e-mail server during her four years as secretary of state. That revelation has spurred separate investigations into whether classified material was mishandled.

The Democrats on the committee said the Benghazi investigation dragged on longer than far more important congressional inquiries like the ones into the Sept. 11, 2001, terrorist attacks, the assassination of President John F. Kennedy, the attack on Pearl Harbor, and the response to Hurricane Katrina.

In a Benghazi report that Democrats issued Monday, they also complained that they had been excluded from the development of the panel’s conclusions.

House Republicans added, inadvertently at times, to the general sense that the committee was focusing too intently on Clinton. Democrats seized on comments by the House majority leader, Representative Kevin McCarthy of California, who boasted on Fox News in September that the committee’s work had put a dent in Clinton’s poll numbers.

“Everybody thought Hillary Clinton was unbeatable, right?’’ McCarthy said. “But we put together a Benghazi special committee, a select committee. What are her numbers today? Her numbers are dropping. Why? Because she’s untrustable. But no one would have known any of that had happened, had we not fought.’’

Those comments helped derail McCarthy’s bid to succeed Speaker John A. Boehner. Gowdy has long disavowed the remarks, saying the discovery of the private e-mail server was highly unexpected and not a focus of his investigation.

There was also internal discord, which led to a former investigator for the committee, Bradley F. Podliska, a major in the Air Force Reserve, filing a lawsuit alleging that he was fired for trying to conduct a thorough investigation into the attacks while superiors wanted to focus on the private e-mail server. The committee said Podliska was fired for cause, including mishandling of classified information.

In the most dramatic confrontation during the two years of the investigation, Clinton testified before the committee for more than eight hours in October, a hearing widely perceived to have backfired on Republicans, as Clinton answered their questions and coolly deflected their attacks.

By the time she testified, Clinton had already taken responsibility for the State Department’s handling of the attacks.