Media playback is unsupported on your device Media caption Protesters take to Capitol Hill

US senators are sparring over an FBI report into sexual misconduct claims against Brett Kavanaugh, President Donald Trump's Supreme Court nominee.

One copy of the report exists for all 100 senators to read. Democrats said it was incomplete and Republicans retorted it did not support the accusations.

Judge Kavanaugh has vehemently denied all allegations against him.

A confirmation vote is expected on Saturday. His appointment would tilt the court in favour of conservatives.

The court's nine justices are appointed for life and have the final say on some of the most contentious issues in US public life, from abortion to gun control and voting laws.

Given Republicans slender 51-49 majority in the Senate, the nominee's fate has hinged on five undecided senators - three Republicans and two Democrats.

Republicans have accused Democrats of seeking to delay the confirmation of Judge Kavanaugh in the hope they will make gains in the mid-term elections in November and stop his appointment altogether.

As senators feuded over the report's findings, police began arresting more than 300 protesters who had gathered in a Senate office building to oppose the nominee.

During a news conference on Thursday afternoon, Judiciary Committee Chairman Chuck Grassley said: "We're just about 48 hours away from having a new person the Supreme Court."

In a statement earlier after reading the report, he said the FBI had "found no hint of misconduct".

Image copyright Reuters Image caption Activists have gathered in the Senate office building to protest Judge Kavanaugh's nomination

What's in the report?

The report contains summaries of interviews that the FBI has conducted. Nine people were reportedly interviewed, but not Judge Kavanaugh, 53, or the woman who first accused him of sexual assault.

It is in paper format only and no copies will be made. It is being held in a secure room in the basement of the Capitol building, known as a Sensitive Compartmented Information Facility, or "Skif".

Senators have been told not to reveal its contents, but some have already begun to describe its findings.

Senator Bob Corker said the report is 46 pages long.

Media playback is unsupported on your device Media caption How US teens talk about sexual assault

Democrats have raised concerns the investigation has been too narrow in scope, with key witnesses not interviewed.

In a letter to FBI Director Christopher Wray on Thursday, the lawyers for the first woman accusing Judge Kavanaugh of sexual assault, Professor Christine Blasey Ford, criticised investigators for not speaking with more than a dozen alleged witnesses whose names she provided.

Has the report swayed undecided senators?

Republican Senator Jeff Flake of Arizona - like other Republicans - said the report contained "no additional corroborating information".

Moderate Republican Susan Collins of Maine said it "appears very thorough".

Another key Republican Senator, Lisa Murkowski of Alaska, told Bloomberg she did not believe that if confirmed Judge Kavanaugh would overturn Roe v Wade, the 1973 ruling that legalised abortion in the US.

They have yet to reveal their voting intentions.

A closely watched Democrat, Heidi Heitkamp of North Dakota, said on Thursday afternoon she would vote against the nominee.

"In addition to the concerns about his past conduct," she said in a statement, "last Thursday's hearing called into question Judge Kavanaugh's current temperament, honesty, and impartiality."

Another key Democrat, Joe Manchin of West Virginia, has yet to declare whether he will support the nominee.

If all Democrats vote against confirming Judge Kavanaugh, Republicans can only afford one defection - since in a tie, Vice-President Mike Pence would have the casting vote.

Image copyright Reuters Image caption Anti-Kavanaugh protesters rally outside the US Supreme Court

What's changed?

Analysis by Anthony Zurcher, BBC Washington

Six days later, the Senate is where it was before the reopened FBI background check of Brett Kavanaugh began. The confirmation vote was, at its heart, a political decision then. It's a political decision now.

The conservative president has his conservative nominee, and the conservative majority in the Senate is predisposed to put that man on the Supreme Court for life.

The biggest sign that this process is heading toward a successful conclusion for Judge Kavanaugh is that, with the investigation concluded, Democrats are fighting about the process by which it was conducted. If there were some explosive revelation, it would have been blasted from the rooftops by now.

Instead, key on-the-fence Republicans like Jeff Flake and Susan Collins are dropping hints they are satisfied with the results. The Senate procedural machinery is grinding toward a final weekend vote.

After all the tumult of the past few days, Judge Kavanaugh could be Justice Kavanaugh by the time the Supreme Court reconvenes next week.

What are the allegations?

Last week Prof Ford testified to the Senate Judiciary Committee that Brett Kavanaugh had assaulted her when they were teenagers in the 1980s.

She said he was drunk and had pinned her on to a bed, tried to remove her clothing and put his hand over her mouth when she screamed.

Another woman, Deborah Ramirez, has accused the nominee of exposing himself to her during a drinking game when they were students at Yale University in the 1980s.

Media playback is unsupported on your device Media caption Christine Blasey Ford said she was "100%" sure Brett Kavanaugh assaulted her

After Prof Ford's testimony, the Senate panel approved Judge Kavanaugh's nomination, but asked for the FBI to conduct further inquiry before the full chamber voted on his appointment to America's top court.

However, the FBI did not examine allegations made by a third woman, Julie Swetnick, that Judge Kavanaugh was involved in the drugging and sexual assault of girls at house parties in the 1980s. He has described that allegation as a "joke".

Why didn't the FBI speak to Ford or Kavanaugh?

The remit of the FBI investigation came from the White House, and some US media reports have said it decided not to ask the FBI to interview Prof Ford or Judge Kavanaugh.

The White House Counsel's office believes that the sworn testimony from both in front of the Senate committee last week is sufficient, CNN reported.