WASHINGTON, United States (AFP) — Democratic Party officials said Friday they have been targeted by a fresh cyber attack, similar to a breach at the Democratic National Committee that resulted in an embarrassing leak of party emails.

The revelation will raise further questions in the United States about the activities of Russian hackers after Hillary Clinton’s campaign blamed Moscow for the initial breach that revealed how party leaders sought to undermine her potential White House rival, Bernie Sanders.

The emails were made public by WikiLeaks and the Kremlin has dismissed as absurd allegations that it was behind the hack. President Barack Obama has refused to rule out that Russia is trying to sway the US presidential election in favor of Donald Trump.

The Democratic Congressional Campaign Committee was the target of a “cyber security incident,” its national press secretary Meredith Kelly confirmed Friday.

“The investigation is ongoing. Based on the information we have to date, we’ve been advised by investigators that this is similar to other recent incidents, including the DNC breach,” she said in a statement.

The DCCC was working to enhance its network security and “cooperating with the federal law enforcement with respect to their ongoing investigation,” she said.

When asked if the two breaches were connected, White House spokesman Eric Schultz referred reporters to the Federal Bureau of Investigation.

“Obviously, they’ve confirmed an investigation into the intrusion at the Democratic National Committee,” he said. “So if there are connected events that they would look at, that would be part of their investigation.”

“Obviously, we expect that investigation to be thorough and deliberate, and to look at all the facts and look at all the fast where they lead.”

US Secretary of State John Kerry raised the DNC hack with his Russian counterpart Sergei Lavrov in Laos earlier this week.

“Secretary Kerry has noted that we’ve been concerned about Russia’s activity in this space for quite some time,” Schultz said Friday. “I suspect that won’t be the last time they have a conversation about this,” he added.

There was no immediate comment from the FBI.