Chanting "no to rescue by blood and fire," families of people kidnapped by Colombian rebels rallied on Tuesday to demand the government hold talks on their release rather than send in troops to rescue them.

The protest followed a decision by President Alvaro Uribe to suspend efforts to reach out to Marxist guerrillas after he blamed them for scuttling a possible accord on hostages by setting off a car bomb in Bogota last week.

Hundreds of hostages have been held by the guerrillas for as long as eight years, including a French-Colombian national and three U.S. contract workers who were captured after their aircraft crashed on a drug eradication mission.

Families fear any rescue attempt by the military will prompt the Revolutionary Armed Forces of Colombia or FARC rebels to kill hostages. They want Uribe to hold talks on exchanging 62 key kidnap victims for rebels in prison, including two leaders imprisoned in the United States.

"We are terrified by the words of the president, terrified by the lack of humanity and consideration," Yolanda Pulecio, mother of hostage Ingrid Betancourt -- a dual French national and former Colombian presidential candidate -- told Reuters at the rally in Bogota's historical city center.

Uribe, a key Washington ally in Latin America, has reduced violence from Colombia's four-decade conflict though a U.S.-backed security crackdown on leftist FARC rebels and a peace deal to disarm thousands of illegal paramilitaries.

But the conflict still ravages parts of rural Colombia where thousands are driven from their homes by the violence every year.

Uribe had been considering a proposal to pull back troops from two municipalities in southern Colombia in an effort to facilitate talks with the FARC, the largest left-wing rebel group.

The conservative president, whose own father was killed by the FARC in a botched kidnapping, had taken a more flexible tone since his re-election in May after Colombians rewarded him for reducing violence. But Thursday's car bomb changed that.

Defense Minister Juan Manuel Santos on Tuesday warned of renewed FARC attacks after Uribe's decision to pull back from talks. The car bomb wounded 10 people at a heavily guarded military base where top generals were attending a ceremony.