A reported threat from an activist hacker group to take protests against Wall Street to the Internet by crippling the New York Stock Exchange Web site appeared to come to nothing on Monday.

A spokesperson for NYSE said there was no interruption to Web traffic and no sign of a hacker attack, although some media outlets reported that the exchange's website slowed for some minutes shortly after 3:30 p.m.

There was no service interruption, said NYSE spokesman Ray Pellecchia.

Pellecchia said the period from 3:35 p.m. to 3:37 p.m. -- reported in some media as the time when the disruption took place -- had been checked. He said there was no sign of an attack on the site.

A video, posted a week ago on YouTube supposedly from a hacker group called Anonymous, threatened to attack the NYSE site: On Oct 10 the NYSE site shall be erased from the Internet, the video said.

The threat was made against the NYSE Web site, not the trading platform, which is used to process billion of share transactions each day. It was not possible to verify the origin of the threat.

Anonymous, reported to be a loose-knit group of hackers, has attracted the attention of law enforcement agencies and media in the past for its protest attacks on corporate and government websites.

The publicized action against the NYSE website was intended as a show of solidarity with the Occupy Wall Street movement that is holding a running demonstration in Zuccotti Park near the NYSE building in Lower Manhattan.

So-called hactivists use distributed denial of service (DDOS) attacks, in which they get supporters to crash the websites of their targets by overwhelming the servers with traffic.

The Anonymous group launched DOS attacks against Visa and MasterCard because the group thought the companies were hostile to Wikileaks and its founder Julian Assange.

(Editing by Bob Burgdorfer)