Abdul Sattar Edhi, Pakistan's best known humanitarian, died in Karachi on Friday night.

From his base in Karachi's inner city, Edhi, who was 88, created a network of social services for his country, including a fleet of 1,500 ambulances, 24-hour emergency services, homeless shelters, orphanages, blood banks and homes for unwanted and abandoned infants. Even during years of agonizing gang violence in Karachi, Edhi frequently drove his own ambulance and showed up personally to transport and care for the injured or wash the dead.

Widely admired for his stubborn integrity — he only accepted private donations, refusing government offers of support — and commitment to helping Pakistan's destitute and forgotten, Edhi was often referred to as " Pakistan's Mother Teresa." He saw charity as a central tenet of Islam and lived humbly with his wife, Bilquis, in the same building as his organization's offices.

But unlike Mother Teresa, Edhi had to operate in the face of death threats and other obstacles. In past years, his ambulances were attacked, as were volunteers who worked for his organization. Islamists occupied one of his Karachi facilities, and the baby cradles he and Bilquis set up to accept unwanted babies were criticized as encouraging out-of-wedlock births.

"They call him an infidel, saying that he does not say his prayers," Bilquis told the Guardian last year. "What we are doing should be done by the government and should be appreciated, but instead we are blamed."

Born in India, Edhi emigrated to Pakistan soon after India's partition in 1947. He started a clinic and a one-man ambulance service in Karachi after the death of his mother, whom he'd cared for during years of illness.

Recalling his early years in Karachi, "I saw people lying on the pavement," he told NPR's Julie McCarthy in 2009. "The flu had spread in Karachi, and there was no one to treat them. So I set up benches and got medical students to volunteer. I was penniless and begged for donations on the street. And people gave. I bought this 8-by-8 room to start my work."

Over the years, this grew into the Edhi Foundation, Pakistan's most relied-upon social safety net, handling many of the responsibilities that the Pakistani government could not or would not.

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