The Denial of Service (DoS) attack involved channelling so much traffic to the web site that viewing the pages became very slow, and at times, impossible. The attacker did not actually hack into YLE's pages.
The initiator and motives for the attack could not be determined. The problems began on Monday at about 3:00 PM and continued late into the evening. The activity continued on Tuesday.
Officials say that it may take six months to find the source of the hostile action, and even then the actual perpetrator might not be caught.
The Finnish Communications Regulatory Authority says that the attack against the YLE web site is the most serious ever on a Finnish web page. A slightly smaller attack recently took place against the Internet security company F-Secure.
Such attacks are often impossible to block. The attacker opens thousands of contacts to the web service that is targeted, or sends thousands of e-mails to the target's e-mail server.
Problems were also reported on the web sites of the Ministry of the Interior and the police. However, these were attributed to maintenance.