Masked attackers armed with pistols and revolvers killed 10 men before dawn Tuesday in two neighborhoods of South America's biggest city, law enforcement officials said.

Six of the victims, aged 15 to 41, were shot several times in the head by assailants who approached them shortly after midnight on a street corner in the poor neighborhood of Parelheiros, said a spokesman for the Sao Paulo Public Safety Department. He declined to give his full name because of department policy.

Two of the victims were still alive when police arrived but died shortly after arriving at the hospital, the spokesman said.

"Police found several empty .40- and .38-caliber bullet shells and a small dish with what appears to be cocaine near the bodies," he said.

About an hour later and some 25 miles away, three masked men approached another group on a street corner in the blue-collar Sao Paulo suburb of Suzano and opened fire. Four men died, and another man and a teenager were wounded but were expected to survive, the spokesman said. Further details of the second killing were not immediately available, he added.

None of the 19 victims were armed, the spokesman said, adding that both "massacres" had the markings of "drug-related settling of accounts."

Asked if the killings could have the work of rogue policemen belonging to death squads, the source said "we cannot discard any possibility."

"The two things that appear certain is that the two incidents are unrelated, because of the distance between the neighborhoods, and that they are not the work of the PCC," the spokesman said using the initials of the First Capital Command, one of Brazil's most notorious organized crime groups.

"The victims were not the kind of people the PCC goes after," he said. "Their targets are usually police officers or other symbols of authority."

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