A 57-year-old man, accused of lending a business owner money at a monthly interest rate of 100 percent, was arrested in Athens yesterday, police said. The businessman went to the police a week ago about his galloping debt after his initial 1,500-euro loan, for one month, grew into a 3,000-euro debt which he could not repay. The alleged loan shark is said to have given his customer two more months to repay the loan but upped his demand to 9,300 euros. The unnamed victim again failed to meet the new payment extension and reported the incident to authorities. Police nabbed the suspect after he was handed the money in marked banknotes. A search of his home revealed evidence suggesting that he was owed close to 150,000 euros by other people.