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VATICAN CITY (Reuters) - Pope Francis condemned “bloodsuckers” who grow rich by exploiting others on Thursday, saying making “slaves” out of workers and setting unfair contracts was a mortal sin.

Francis, who frequently speaks of his concern for the poor, appeared to be referring to the kind of grueling labor often done by poor migrants in rich countries across the world, but also to many other workers on precarious contracts.

During mass at the Vatican, he told a story about a girl who found a job working 11 hours a day for 650 euros ($729) a month, paid “under the table”.

“This is starving the people with their work for my own profit! Living on the blood of the people. And this is a mortal sin,” he said at the service in his Santa Marta residence.

“Without a pension, without health care ... then they suspend (the contract), and in July and August (the workers) have to eat air. And in September, they laugh at you about it. Those who do that are true bloodsuckers.”

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