High-tech crooks using spyware are costing U.S. discount brokerages millions of dollars to repay clients who have been victimized by fraud, the brokerages said in recent days. The U.S. Securities and Exchange Commission warned earlier this month that scammers were hijacking online brokerage accounts using spyware and operating from remote locations. TD Ameritrade has said that it cost $4M in their third quarter from customers whose accounts had been hacked. Harder hit was rival E*Trade Financial Corp., which last week said its fraud losses ballooned by $18 million in the third quarter from swindlers who stole clients’ identities and manipulated their accounts.