WASHINGTON • A US intelligence contractor has been charged with sending a classified report alleging Russian interference in last year's election to the news media, the first criminal leak case under President Donald Trump.

The case shows the Justice Department's willingness to crack down on leaks, after Mr Trump's claim that they were undermining his administration.

The department announced on Monday a charge under the Espionage Act against Reality Leigh Winner, 25, about an hour after national security news outlet The Intercept published the apparent document, a May 5 intelligence report from the National Security Agency (NSA).

The report described two cyber attacks by Russia's military intelligence unit, the GRU - one in August against a company that sells voter registration-related software, and another a few days before the election against 122 election officials.

The Justice Department said the Federal Bureau of Investigation (FBI) arrested Winner last Saturday. It also said she had confessed to printing a file mailed to an online news outlet.

An FBI affidavit said reporters had approached the NSA with questions for their story and provided a copy of a document.

The NSA's auditing system showed that six people had printed out the report, including Winner. Investigators examined the computers of those six and found that Winner had been in e-mail contact with the news outlet.

The Kremlin yesterday denied that Russian military intelligence hackers had tried to infiltrate US voting systems.

NYTIMES, AGENCE FRANCE-PRESSE