Simpson has not been arrested or indicted.
Agents arrived at about 6 a.m. and Simpson was at home. In a shot from a television helicopter, Simpson could be seen walking in the backyard in a bathrobe. About two hours after agents arrived, Simpson left the home alone in his sports utility vehicle without talking to reporters.
Judy Orihuela, a spokeswoman for the FBI's Miami office, said she could give no details of why Simpson's house was searched or what agents were looking for. "He's not named in the indictment and he's not been arrested," she said.
The U.S. Attorney's Office had no comment yet on the case.
Simpson attorney Yale Galanter arrived at the house and spoke to agents for about 15 minutes. He later spoke to reporters saying, "Mr. Simpson and I fully cooperated with the investigation." He said no illegal drugs where found in the house or in Simpson's car, and said that his client was not involved in money laundering.
Simpson, 54, who parlayed a spectacular run in the National Football League into a career as a sportscaster, TV pitchman and actor, was charged in 1994 with the slashing deaths of his ex-wife Nicole Brown Simpson and her friend Ronald Goldman. He was acquitted after a lengthy criminal trial but was later found liable for their deaths in a civil case and ordered to pay $33 million.
Just six weeks ago, he was acquitted in a road rage case, found not guilty by a Miami jury of auto burglary and battery in a case that could have landed him in prison for up to 16 years.
His October trial involved an incident in which Simpson was accused of grabbing another driver's glasses and scratching his face in a traffic dispute in Kendall last year.
The FBI said the search by the FBI, Miami police and agents from the Drug Enforcement Administration, which included sniffer dogs, was related to a suspected drug ring that allegedly brought ecstasy pills from Europe into Miami's club scene. Eleven people were indicted in the case Tuesday.
Orihuela said the group stole equipment used to counterfeit cards that activate satellite television receivers. She also said the ring laundered about $800,000.
Orihuela said that of those indicted, nine had been arrested and were in custody and two were at large, one in south Florida and the other in Brazil.
A 10th person who was not named in the indictment but who was with one of the suspects, was also arrested, she said.
In addition to Simpson's home, searches were taking place in eight other places in the Miami area, Orihuela said.
Two of those arrested were detained in Chicago, one of them with $75,000 in cash on him. Another of the people arrested was detained in the Miami area Monday night after allegedly offering to sell an undercover gent a batch of 8,000 ecstasy pills. The pills are worth about $5 each wholesale and $20 on the street.
Most of those indicted were from the United States, but two were from Brazil, Orihuela said.
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