Hackers attacked the European Commission's computers on Thursday, flooding the EU executive's servers with digital service requests, but while connection speeds were affected, there was no data breach, the Commission said.
"Yesterday afternoon the Commission was targeted by an attempt to saturate our internet connection," Commission spokesman Margaritis Schinas told a news briefing on Friday.
"The commission took effective counter-measures and there was no interruption of service, although connection speeds were affected for a while, there was no data breach," he said.
Schinas said the Commission did not know who was behind the attack, which was of the distributed denial of service (DDoS) type when too many simultaneous requests to servers cause the service to crash.
The attack happened as Ukrainian President Petro Poroshenko visited Brussels to discuss visa free travel to the EU. Schinas declined to comment if there was any connection between the attack and the visit.