WASHINGTON • Computer systems used by Mrs Hillary Clinton's presidential campaign were hacked in an attack that appears to have come from Russia's intelligence services.
The apparent breach, coming after the disclosure last month that the Democratic National Committee's computer system had been compromised, escalates an international episode in which Clinton campaign officials have suggested that Russia might be trying to sway the outcome of the election.
Mrs Clinton's campaign said in a statement that intruders had gained access to an analytics program used by the campaign and maintained by the national committee, but it said that it did not believe the campaign's own internal computer systems had been compromised.
The Democratic Congressional Campaign Committee, the fund- raising arm for House Democrats, also said last Friday that its systems had been hacked.
Together, the databases of the national committee and the House organisation contain some of the party's most sensitive communications and voter and financial data.
It's the same adversary. These are sophisticated actors.
THE OFFICIAL INVOLVED IN THE FORENSIC INVESTIGATION, on the people behind the attack on the congressional committee's system.
Ms Meredith Kelly, a spokesman for the congressional committee, said that after it discovered the breach, "we immediately took action and engaged with CrowdStrike, a leading forensic investigator, to assist us in addressing this incident". The attack on the congressional committee's system appears to have come from an entity known as "Fancy Bear", which is connected to the GRU, the Russian military intelligence service, according to an official involved in the forensic investigation.
The same arm of Russia's intelligence operation was also implicated in the attack on the Democratic National Committee, in which it gained access to opposition research on Republicans, including the party's presidential nominee, Mr Donald Trump. "It's the same adversary," the official involved in the forensic investigation said.
"These are sophisticated actors."
The Federal Bureau of Investigation said it was examining reports of "cyber intrusions involving multiple political entities" but did not identify the targets of the attacks.
The Clinton campaign used the program that was hacked to analyse voter data, but it did not contain voters' Social Security numbers or credit card information, a campaign aide said.
The reports of attacks against Democratic Party organisations began in mid-June, when the Democratic National Committee said its computer systems had been breached by two groups of Russian hackers working for competing government intelligence agencies. After that breach, WikiLeaks last week released some 20,000 committee e-mail messages, many of them embarrassing to Democratic officials, which led to the resignation of Ms Debbie Wasserman Schultz, a Florida congressman, as the group's leader.
Clinton campaign officials have suggested that President Vladimir Putin could be trying to tilt the election in favour of Mr Trump, who has expressed admiration for the Russian leader. But the campaign officials acknowledge that they have no evidence. The Trump campaign has dismissed the accusations about Russia as a deliberate distraction.
NEW YORK TIMES