By TONY SMITH

Scores of police officers from across Rio de Janeiro were surrounding shantytowns on the city's northern outskirts last night in an effort to contain brutal gang
warfare that has left at least nine dead in two days of battles involving the police and rival drug gangs.

Maj. Roberto Edelman of the 16th Battalion of the city police said in a telephone interview that the conflict started on Tuesday night when members of the Third
Command gang, which controls the shantytown known as Parada de Lucas invaded a neighboring slum, Vigário Geral, run by the notoriously ruthless Red Command, which controls much of the city's drug trade.

Residents said nine people were kidnapped in the raid by gang members disguised in police uniforms. Six bodies were found in a nearby river early yesterday, Major
Edelman said. As yet, the bodies had not been identified, he said.

Gang members from Vigário Geral, backed by at least 50 allies from other shantytowns, launched a counter-attack on Parada de Lucas early yesterday and the police intervened, killing three gang members, taking six prisoners and seizing several automatic weapons, pistols and a cache of ammunition.

"This is open warfare, like between two countries," said Major Edelman. "We expect something else will happen tonight."

He said police units from as many as seven battalions had been called in to ring the two neighborhoods and some other areas of the city that were supplying the Red
Command with reinforcements.

Rio's hillside slums are virtual fortresses for the heavily armed gangs that control the lucrative drug trade and frequently outnumber and out-gun the police. Earlier this
year, just before the city's world-famous carnival celebrations, drug gangs ran riot in the city, torching buses, attacking police stations and favorite tourist spots,
prompting the government to call in army troops to keep the peace.