Two Israeli teenagers have been arrested on suspicion of running a service that allowed paying customers to attack websites.
The vDos service the pair are suspected to have run bombarded target sites with data, seeking to knock them offline.
The vDos website went offline shortly before the men were taken into custody.
The arrests came soon after cybersecurity expert Brian Krebs posted a lengthy article claiming to expose the controllers of the vDos service.
But an Israeli police spokesman told Israeli newspaper Haaretz the arrests had come after a tip-off from the FBI.
Haaretz and The Marker reported that Itay Huri and Yarden Bidani, both 18, had been put under house arrest for 10 days.
Both had posted a bail payment of about $10,000 (£7,500).
And they had had to surrender their passports and were barred from using the net or any other communication device for 30 days.
Mr Krebs said he had based his article on a cache of information stolen from the service that he said had been passed to him by an informant.
The two men named in the stolen information as controllers of vDos have the same names as the two people arrested in Israel.
Mr Krebs claimed the site’s controllers had been “not terribly careful to cover their tracks” , using email addresses and phone numbers on sites connected to vDos that could be directly connected to them.
He said the stolen data indicated the vDos service had generated $600,000 over the past two years by helping to co-ordinate more than 150,000 distributed denial of service (DDoS) attacks.
And vDos had charged between $30 and $200 a month for each attack.
Mr Krebs wrote: “To say that vDos has been responsible for a majority of the DDoS attacks clogging up the internet over the past few years would be an understatement.”
Mr Krebs’s site came under a heavy DDoS attack soon after the article about vDos was published.
The UK’s Imperial College, game site GoodGame.co.uk and security company Zare.com were reportedly victims of vDos sourced attacks.
One quirk of the service was that it had a policy of never attacking websites located in Israel.