Hackers compromised the computer systems of the Republican National Commitee last week, around the same time the Florida-based software vendor Kaseya was hit by a REvil ransomware attack, Bloomberg reported, citing people familiar with the matter.

The attack was launched by a threat actor affiliated with the Russia-linked APT 29 (or Cozy Bear) hacking group, which previously was accused of breaching the Democratic National Committee in 2016 and of carrying out a supply chain cyberattack involving SolarWinds Corp that came to light in December last year.

It’s not clear if the hackers stole or viewed any data. The RNC has repeatedly denied that it was hacked. “There is no indication the RNC was hacked or any RNC information was stolen,” spokesman Mike Reed said.

In a statement Chief of Staff Richard Walters said the RNC learned over the weekend that a third-party provider Synnex Corp was hacked.

“We immediately blocked all access fr om Synnex accounts to our cloud environment,” he said. “Our team worked with Microsoft to conduct a review of our systems and after a thorough investigation, no RNC data was accessed. We will continue to work with Microsoft, as well as federal law enforcement officials, on this matter.”

The sources told Bloomberg that the hackers may have targeted the RNC through Synnex.

In a statement the California-based company has confirmed that it is “aware of a few instances wh ere outside actors have attempted to gain access, through SYNNEX, to customer applications within the Microsoft cloud environment. These actions could potentially be in connection with the recent cybersecurity attacks of Managed Service Providers, or MSPs.”

“While SYNNEX provides many services as part of its overall IT distribution business, including supporting Microsoft cloud applications, it is not an MSP in the context mentioned in recent media,” the company said.