Voting at the NDP leadership convention in Toronto was disrupted Saturday by what organizers called a malicious attempt to shut down the computer system.

Party members were frustrated during voting on the first ballot, as thousands across the country tried to log on and cast ballots using the Internet.

Earl Hurd of said he believes someone used a "denial of service" program to disrupt the voting paralysing the central computer by bombarding it with a stream of data.

"If you think about going to the supermarket and somebody continually cuts ahead of you in line, and you never get to the checkout counter, what this person has done is write a computer program that says 'I am going to perpetually get somebody ahead of everybody else in the queue,'" Hurd explained.

"We had one log-in attempt that corrupted the ability of everybody to get access to our servers," he said.

By the time the problem was resolved, voting was at least 45 minutes behind schedule. Results were not released until just after 4:30 p.m.

Toronto city councillor Jack Layton's victory on the first ballot surprised many, who had expected a second or even third round of voting before a leader was chosen from the pack of six candidates.

Hunt for culprit

When asked if a second ballot might be delayed by another act of computer vandalism, conceded that the culprit might strike again.

"Unless he died in the last few minutes because of the evil thoughts in my brain, he or she is still out there," Hurd said, laughing.

Security measures stopped anyone from actually busting through the computer's defensive perimeter and altering results, he added. The only problem was a delay in the voting, Hurd said, and steps had been taken to try to block another "denial of service" attack.

Investigators hope to track down the person who targeted the site and prosecute them.

A majority of party members cast their ballots ahead of time, either by mail or on the Internet. But thousands waited until Saturday afternoon to vote either at the convention or through e-mail.

It is the first time "real-time" Internet voting was used in a major Canadian leadership vote, according to organizers.

Although some people questioned the wisdom of relying on computer technology, others pointed out that delegates were able to cast ballots from home only minutes after listening to the candidates' final speeches something that they argued allows more people to feel part of the weekend convention.