Brazil's police say they have broken up a gang suspected of carrying out about 1,000 contract killings in five years.
Local police officers are suspected of involvement in the gang
At least 20 people, including police officers, businessmen and hired gunmen, were arrested in the north-eastern state of Pernambuco.
Police described the gang as "Murder Incorporated" - a professional business operation hired to kill people over small debts, and out of revenge.
The north-eastern state of Pernambuco has the highest murder rate in Brazil.
Death squads involving serving and retired police officers have long been a problem in Brazil where shop-keepers sometimes use them against street children.
Police say the gang was a professional organisation which carried out around four killings a week for between $500 and $2,500 each (£252-1260).
It was believed to have been hired - often by local merchants - for motives which the police described as banal. Some of the victims had debts to loan sharks, others were simply caught up in personal disputes, like rows over women.
The federal police chief in Pernambuco, Jorge Pontes, said the gang operated like a business prepared to take on absolutely any killing.
"This group practises what we in the police call 'general hospital'. We were suddenly faced with this homicide company," he said.
"Many times the victims were killed because of loan sharks, they owed money."
The organisation is believed to have used local police officers to cover up its activities by removing evidence from crime scenes.
Earlier this week, another death squad was broken up in Pernambuco's capital, Recife.
The BBC's Simon Watts says the sad fact is that life is cheap in a poor state with a long history of violence in cities and rural areas.
He says victims are often street children or small-time thieves regarded as social undesirables. Local police are either directly involved or else turn a blind eye, while convictions are rare.
Campaigning prosecutors in Brazil have called these arrests a big step forward - but they say many more operations of this kind are needed.