BOSTON—Republican Sen. Jeff Flake told a crowd here Monday the FBI should do “a real investigation” into sexual-assault allegations against Supreme Court nominee Brett Kavanaugh, saying “we are working to make sure that happens.”

“It does no good to have an investigation that just gives us more cover,” the Arizona senator said at the Forbes Under 30 Summit, a gathering of young entrepreneurs and leaders in industries from finance to fashion. “We actually need to find out what we can find out.”

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