NEW YORK (AP) — A computer expert engineered a more than $4 million theft from Columbia University by manipulating its bill-paying system, and he used some of the money to buy himself an $80,000 car, prosecutors said.

George Castro is fighting the charges, and “we expect that he’ll be vindicated,” his lawyer, David N. Fisher, said Monday.

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According to prosecutors, one of Columbia’s accounts was altered in October to channel money illicitly into an account in the name of Castro’s information technology business.

The account collected more than $4.4 million — then withdrawn in cash or transferred to other accounts controlled by Castro — before his arrest last week at his Bronx home, a court complaint says.

Found with $200,000 in cash on him and his $80,000-plus Audi parked outside, Castro, 48, told a police officer: “The money just appeared in my account,” according to the complaint.

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“I got greedy” and bought the car and other items, he added, according to the complaint.

His connection to the Ivy League university is unclear. Its directory doesn’t list him as an employee.

A Columbia spokesman declined to comment on the ongoing investigation, except to note that the university had brought the matter to authorities.

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