The idea was born less than a month ago on the social networking Web site Facebook: marches across Colombia to denounce the country's main leftist rebel army.
Nearly 100,000 people in 165 cities across the world have confirmed their participation on Facebook for Monday's march under the banner, "No more kidnappings! No more lies! No more deaths! No more FARC!".
"We hope the whole country will come out to join us," said Cristina Lucena, a 24-year-old political science student from Bogota and one of the protest's six main organizers.
But instead of uniting citizens against the rebel Revolutionary Armed Forces of Colombia, Monday's mobilization has exposed deep divisions over how to end the decades-long conflict that precedes the nation's cocaine wars.
Many families of the hostages _ who in some cases have been held for more than 10 years _ fear that protesting the FARC could endanger their loved ones.
Others argue the march should encompass all violent armed groups, including far-right militias critics say are backed by politicians in President Alvaro Uribe's camp.
"I doubt that the victims of the paramilitaries have their own select club on Facebook," columnist and government critic Maria Jimena Duzan wrote in the largest national daily _ a reference to death squad victims concentrated in Colombia's impoverished countryside.
The marches were conceived after a particularly grueling month in Colombia's conflict with rebels out to topple the government and redistribute wealth. The FARC freed two hostages _ but with them came letters and pictures detailing debilitating illness and deprivation in barbed wire-ringed jungle camps.
Among the remaining hostages are three U.S. military contractors and former presidential candidate Ingrid Betancourt.
"We felt we were drowning. We needed to do something," Lucena said.
The FARC called the march an attempt to bolster its enemy, Uribe.
"If the suffering of those in captivity has been unjustifiably prolonged ... this has been because of the inhuman intransigence and worthless pride of President Uribe," rebel leaders said in a statement released Friday.
For weeks, invites to the march flew through cyberspace, mainly among the typically young _ and relatively wealthy _ who crowd Facebook in a country where only about one in four can afford to use the Internet regularly.
Colombia's media caught wind quickly and immediately endorsed it in grand style. Street vendors made T-shirts with the march's motto and hawked them on Bogota's streets.
Criticism of march's focus
But as momentum grew _ with rallies planned from London to New York, Paris and Tokyo _ so did criticism of the march's narrow focus.
The left-wing Polo Democratico party said it would hold a separate rally on the same day to reject all terrorism _ whether it's caused by rebels, Colombian soldiers killing innocent peasants or far-right death squads.
In a country where virtually everyone knows someone who has been killed, forcibly displaced or kidnapped, discussions on how to end the conflict quickly get emotional.
The opinion pages of El Tiempo, Colombia's largest daily, have seethed with the controversy.
Duzan suggested the march could encourage Uribe to seek a third term. The government has endorsed Monday's march and even sent out a list of meeting points for protesters across the globe.
Angry letters to the editor suggested Duzan sit out the march, and an editorial in Thursday's El Tiempo savaged those clamoring for a different focus in the march as "cynical" and "shameless."
Lucena rejects the notion that the marches were organized by or will be dominated by the wealthy. Future marches might well target other armed groups, she said.
"We've had many marches for peace, but that's a huge complicated issue. ... This time we wanted a very clear objective to our march: no more FARC."
Associated Press writer Tatiana Guerrero in contributed to this report.