After convicted spree killer Nicholas T. Sheley picked up four more life prison sentences Monday, all eyes are now on prosecutors in Missouri, where Sheley is charged with two more murders.

Sheley, 35 of Sterling, Ill., is charged with two counts each of first-degree murder and armed criminal activity in connection with the deaths of Jill and Tom Estes, both 54, of Sherwood, Ark.

Prosecutors say Sheley encountered the couple, who were in town for a family graduation, the night of June 29, 2008, at their hotel.

Their bodies were found a day later behind a nearby gas station.

Jefferson County Prosecuting Attorney Forrest Wegge said Monday that he has been waiting for the Illinois prosecutions of Sheley to end before he begins the extradition process to bring the suspect to Missouri.

Wegge said "each extradition is unique" and that it would be "pure speculation" at this point to estimate how long it will take to get Sheley to Missouri.

"If he waives (extradition), then it goes fairly quickly," Wegge said. "If he doesn't, then it doesn't go quickly."

Wegge said he has stayed in frequent contact with Illinois prosecutors as those cases made their way through the state's courts.

Galesburg attorney Jeremy Karlin has represented Sheley in all of his Illinois cases.

Because his representation of Sheley is now over, Karlin said Monday that he does not think he will be involved in the extradition process.

Karlin also said he did not know whether Sheley plans to waive or fight extradition.

Maura Possley, a spokeswoman for the Illinois Attorney General's Office, referred questions to Wegge.

Sheley was sentenced Monday to consecutive life terms in the deaths of Brock Branson, 29, his girlfriend, Kilynna Blake, 20, her 2-year-old son, Dayan, and Kenneth Ulve, 25, all of Rock Falls.

Sheley also is serving life without parole in the deaths of Russell Reed, 93, of rural Sterling, and Ronald Randall, 65, of Galesburg.

Prosecutors say Sheley killed the eight people during a drug- and alcohol-fueled spree in late June 2008.