Hundreds of locals converged for eight minutes in the card section of the Harvard Coop yesterday evening in the first-ever Internet-organized "flash mob" to be held in New England.

News cameras weaved among a densely packed crowd and photographic flashes flickered over a sea of DaVincian smiles on the second floor of the Harvard Coop yesterday evening as local media turned out to watch hundreds of Boston-area residents pick out greeting cards for their friend Bill.

The first “flash mob” in New England gathered in Harvard Square yesterday, bringing one of the newest and quirkiest Internet fads—and the portent of a new sort of sociological phenomenon, some say—to Cambridge.

The first flash mob, a spontaneous and momentary convergence of people at a predetermined location, was held in June in New York City. Since that time, similar events have been organized throughout the United States and western Europe.

Yesterday’s flash mob, like each of its national precedents, was organized over the Internet—in this case, through an anonymously moderated Yahoo group called “bostoncitymob,” which boasted over 600 subscribers as of last evening.

Most of the participants in yesterday’s mob said they had heard about the organization list from a friend, or heard about the coming event through the media.

“I read about it in the newspaper and it seemed like an interesting thing to do and good, harmless fun,” said Matt Fonts, a public accountant from Somerville, as he and a friend wended their way toward the Palmer Street Coop in preparation for the public stunt.

“It doesn’t really have a goal. It’s just something unusual and whimsical,” said Claudia Mastroianni ’91-’94, a computer technician at the University who helped with low-level organization for the event.

The Harvard Square mob somewhat lacked the element of surprise that its precedents sought. Most flash mobs spurn media attention, aiming toward the semblance of inexplicable spontanaeity. A small entourage of news reporters attended yesterday’s crowd.

But the stunt stayed true to its principles of surprise and whimsy. No one but the organizers—not even participants—knew what it would entail until exactly 12 minutes before it began.

A series of dispatches from “Bubb Rubb & Lil’ Sis,” the mob’s anonymous masterminds, sent over the mailing list beginning mid-July outlined the parameters for participation.

After synchronizing their watches to the government time zone website, participants converged at one of five satellite locations throughout the Square, depending on their birthdays, between 6:43 and 6:57 p.m.

Participants born in May or October, for instance, met at the bar of the Border Cafe. Those born in January or July crowded around the table nearest the bathrooms of Au Bon Pain. They had no further instructions.

At 6:51 p.m. the growing crowd murmuring uneasily in the right wing of the Au Bon Pain dining area stirred into motion. Mastroianni was dispersing half sheets bearing final instructions for the mob.

She said she had responded the previous week to an invitation to help distribute instructions that the “bostoncitymob” administrators had sent over to the group.

Trying at once to be inconspicuous and to squeeze past the conflux of bodies pushing toward the tiny table where Mastroianni sat, participants clutching the seven-step instructions stumbled out of the eatery and into the Holyoke plaza.