You have to admire the balls of a group of German hackers who dub themselves XMR Squad.

The outfit spent all last week launching DDoS attacks against German businesses and then contacting the same companies to inform them they had to pay $275 for ‘testing their DDoS protection systems.

Attacks were reported against DHL, Hermes, AldiTalk, Freenet, Snipes.com, the State Bureau of Investigation Lower Saxony, and the website of the state of North Rhine-Westphalia. The attack against DHL Germany was particularly effective as it shut down the company’s business customer portal and all APIs, prompting eBay Germany to issue an alert regarding possible issues with packages sent via DHL.

While the group advertised on Twitter that its location was in Russia, a German reporter who spoke with the group via telephone said: “The caller had a slight accent, but spoke perfect German.”

Following the attention it got in Germany after the attacks, the group had its website and Twitter account taken down.

Hackers mocked the group for failing to extract any payments from their targets. DDoS extortionists have been particularly active in Germany, among any other countries. Previously, groups named Stealth Ravens and Kadyrovtsy have also extorted German companies, using the same tactics perfected by groups like DD4BC and Armada Collective.