O. J. Simpson was charged Sunday with six felonies in connection with a reported armed robbery of sports memorabilia in a Las Vegas hotel room on Thursday night, the Las Vegas police said.

Mr. Simpson was booked into the Clark County Detention Center and charged with two counts each of robbery with a deadly weapon and assault with a deadly weapon, as well as one count each of conspiracy to commit burglary and burglary with a firearm, Lt. Clint Nichols of the Las Vegas police said. A judge ordered Mr. Simpson held without bail pending arraignment this week in Clark County Justice Court, possibly via video.

The top two charges carry sentences of 3 to 35 years each and, by state law, would have to be served consecutively, so Mr. Simpson faces 6 to 70 years on those alone, the authorities said.

A group of six people that included Mr. Simpson are accused of storming into a room at the Palace Station Hotel and Casino a mile from the Las Vegas Strip about 8 p.m. Thursday. Another member of the group, Walter Alexander, 46, of Mesa, Ariz., was arrested late Saturday and was charged with the same counts. He was released early Sunday on his own recognizance, said his lawyer, Robert Rentzer.

The police are seeking the other four members of the group and have identified three of them: Clarence Stewart, 53, of Las Vegas; Michael McClinton, 49, of Las Vegas; and Tom Scotto, age and hometown unavailable.

It remained unclear exactly what property was taken and to whom it belonged.

“Having said that, the manner in which these properties were taken, we have a responsibility to look into that regardless of who the property belongs to,” Lieutenant Nichols said. “We also have some information that the property that Mr. Simpson allegedly took was not his property.

“It included a lot of sports memorabilia and most of it had been signed by Mr. Simpson himself along with some other property,” Lieutenant Nichols said. “I believe there were some Joe Montana cleats, some signed baseballs and some other stuff.”

Capt. James Dillon of the Las Vegas police said investigators had confiscated two guns that might have been used in the Thursday incident in a morning raid on three locations.

Mr. Simpson, 60, was arrested at the Palms Resort Casino, was taken to police headquarters for questioning at about noon and was transferred to the detention center in late afternoon. Police officials said he would spend the night in isolation in a small cell.

Mr. Simpson has declared his innocence, telling The Associated Press that there had been no guns involved in what he called a self-organized sting operation intended to retrieve some of his football memorabilia.

Mr. Alexander, 46, of Mesa, Ariz., was arrested at McCarran International Airport here as he prepared to fly to Los Angeles to meet with Mr. Rentzer, the lawyer said.

Mr. Rentzer, who defended Rodney King on his traffic arrest in 1991, said Mr. Alexander had been released on bond about 4 a.m. Sunday.

“I assured the authorities that we are not hiding and that he will be available to us,” Mr. Rentzer said. “Until I can meet with my client and hear the facts of the case and determine my client’s exposure, I refuse to discuss the prospects of plea bargaining.”

Two memorabilia dealers, Alfred Beardsley of Glendale, Calif., and Bruce L. Fromong of North Las Vegas, Nev., told the police on Thursday that a group of men, including two with guns, entered Mr. Beardsley’s hotel room around 8 p.m. and left with a trove of sports memorabilia. They said the items had included photographs and books signed by Mr. Simpson, lithographs of the former San Francisco 49ers quarterback Joe Montana and Mr. Beardsley’s cellphone.

Mr. Beardsley and Mr. Fromong told the police that Mr. Simpson had directed the group.

In his interview with The A.P., Mr. Simpson gave a different account. He said that he and some acquaintances had left a cocktail party and gone to Mr. Beardsley’s room, escorted by Tom Riccio, an auction house owner.

Mr. Simpson said he had pretended to be interested in buying the suit that he wore in court in 1995 when he was acquitted of the murders of his former wife, Nicole Brown Simpson, and her friend Ronald Goldman. The group left with Mr. Simpson’s Football Hall of Fame certificate and a photo of J. Edgar Hoover, the former Federal Bureau of Investigation director, among other items, Mr. Simpson said.

“Everybody knows this is stolen stuff,” Mr. Simpson was quoted as saying. “Not only wasn’t there a break-in, but Riccio came to the lobby and escorted us up to the room.”

“In any event,” he was quoted as saying, “it’s stolen stuff that’s mine. Nobody was roughed up.”

Mr. Simpson was acquitted for the 1994 double murder, but he was found liable for the deaths in a civil case in 1997 and was ordered to pay the Goldman family $38 million and Ms. Simpson’s family $24 million. To date, he has paid about $10,000 of the judgment, said a lawyer for the Goldman family, David J. Cook.

The Goldman family has watched the Las Vegas case with “cautious optimism,” said Mr. Goldman’s father, Fred Goldman.

“He deserves whatever he gets,” Mr. Goldman said.