NYT:

The mystery surrounding a Russian intrusion into Florida’s voter registration systems during the 2016 election deepened on Tuesday when Gov. Ron DeSantis said that the F.B.I. had revealed to him which counties in the state had been targeted — then required the governor to keep the information secret.

At a news conference in Tallahassee, Mr. DeSantis, a Republican, said that officials from the F.B.I. and the Department of Homeland Security had asked him to sign a nondisclosure agreement pledging not to identify the two counties that fell victim to a “spearphishing” attempt by Russian hackers.

That the Russians breached security protocols in not one but two counties was previously unknown. Last month, the Mueller reportconfirmed that the F.B.I. believed that the Russian military intelligence unit known as the G.R.U. breached “at least one Florida county government.” Elections officials said that if the intrusion came through a spearphishing email, as it apparently did, it would put hackers in a position to potentially alter registration data, though not the tabulation of ballots….

That the governor was asked to sign a nondisclosure agreement to receive classified information is not unusual. The F.B.I. makes similar requests of police chiefs when discussing cases involving classified terrorism threats, for example. Typically, the F.B.I. does not release the names of hacking victims for privacy reasons.

Less clear is why information, the gist of which has already been made public in the Mueller report, would be deemed too sensitive for public disclosure. There was an immediate flood of questions on social media, with many wondering how the public could feel confident that the voter rolls had not been tampered with and that local elections supervisors had taken the necessary steps to prevent a similar hack in the future — without knowing which counties had been breached.

“This is not acceptable, to keep secret attacks on the most public of our political processes: our elections,” said Ion Sancho, a Democrat and the former elections supervisor of Leon County, which includes the state capital, Tallahassee.