Two 18-year-old cousins have been charged in the death of a former Saint Louis University volleyball player, who was shot twice during an attempted robbery, the St. Louis Circuit Attorney's office announced Friday.

Keith V. Esters, of Bel Ridge, and Johnathan Perkins, of St. Louis, were charged in the death of 23-year-old Megan Boken of Wheaton, Ill., St. Louis Circuit Attorney Jennifer Joyce said.

Esters was charged with first-degree murder, first-degree attempted robbery and armed criminal action. Perkins was charged with second-degree murder, second-degree attempted robbery and armed criminal action. Both suspects have been in custody without bond since Thursday. Online court documents did not list lawyers for either suspect.

Boken was shot twice, in the chest and the head, while sitting in her car Saturday afternoon in the Central West End, according to a probable cause statement filed with the charges. Boken was in town for a Saint Louis University alumni volleyball game, and she graduated from the school last year with a bachelor's degree in business administration.

The probable cause statement said investigators were led to Esters and Perkins by a cellphone that was connected to another robbery in the same area.

"That investigation led to a witness who stated that her boyfriend, Keith Esters, admitted to her that he was involved in the shooting of Ms. Boken," the statement said. "The witness also stated that her boyfriend and his cousin, Johnathan Perkins, made plans to drive to the Central West End and commit a robbery."

Perkins also told police that Esters saw Boken speaking on her cellphone and decided she "would be the target of the robbery," according to the statement from police. She was killed during the course of the robbery, the statement said.

Steve Capizzi, assistant circuit attorney, said Friday that both suspects would likely be arraigned early next week, and that it appeared neither had previous records in Missouri.

Capizzi also said the circuit attorney's office has been in contact with the Boken family, who are "still in a state of remorse and shock."

Boken's family said in a statement released Thursday after the suspects were arrested they were "gratified with the progress in this case and with the efforts of the St Louis Police Department." Boken was buried Thursday in Wheaton.