A hacking and extortion gang has taken credit for a cyberattack and data breach at Uber Freight, the ride-sharing giant’s logistics subsidiary.

A spokesperson for Uber Freight told Reuters, which first reported the incident, that there was no effect on its business operations and that its systems were running normally (The company did not immediately respond to TechCrunch’s questions about the incident.)

The shipping company is the latest victim in a spate of hacks in recent weeks conducted by the Helix hacking group, which has targeted transportation companies, financial giants, and private equity firms throughout the year. The hackers are known for targeting companies and exfiltrating large amounts of data from their cloud environments, which they then threaten to publish if the victim companies do not pay a ransom.

In a post on its data leak site, which it uses to host the stolen files, the Helix hackers claim to have taken mailboxes, cloud storage drives, files relating to accounts payable and dispatch documents from Uber Freight.

Some of the files seen by TechCrunch appear to show email correspondence between Uber Freight and several of its customers. TechCrunch could not immediately verify the authenticity of the files, which appeared to be dated around mid-June.