NEW YORK — Facebook set off a firestorm Tuesday, announcing that it had uncovered “sophisticated” efforts, possibly linked to Russia, to manipulate U.S. politics and by extension the upcoming midterm elections.

The company was careful to hedge its announcement; it didn’t connect the effort directly to Russia or to the midterms, now less than 100 days away. And its findings were limited to 32 apparently fake accounts on Facebook and Instagram, which the company removed.

But official Washington went ballistic anyway, not least because the reported activity so closely mirrored Russian influence efforts during the 2016 presidential election. Nearly 300,000 people followed at least one of the newly banned accounts and thousands expressed interest in events they promoted.