The mother of one of the LDS Church missionaries kidnapped in Russia and later released said her son is doing fine and she is waiting for a phone call from him Friday or Saturday.

Police, in the meantime, are releasing more details of the kidnapping scheme, saying a man they arrested engineered the abduction and is a disassociated church member, according to Interfax News Agency.The man, whose name has not been released, was arrested in Saratov, a city 450 miles southeast of Moscow on the Volga River. Elders Andrew Lee Propst, 20, of Lebanon, Ore., and Travis Robert Tuttle, 20, of Gilbert, Ariz., were assigned as missionaries there for The Church of Jesus Christ of Latter-day Saints.

"The boys are doing just fine," said Mary Propst, Andy Propst's mother, from the family home in Oregon Thursday. She and her husband, Lee, only got to speak to their son for several minutes Sunday after learning of his and Tuttle's release. Church officials have kept them updated as to developments since then and have given her hope she can speak to her son again Friday or Saturday.

Vladimir Terentyev, deputy chief of the regional branch of the Federal Security Service; and Sergei Boldyrev, head of the branch's Investigation Department, held a press conference in Saratov Tuesday and described the arrested man as an up-and-coming businessman, born in 1954, who "co-founded a branch" of the LDS Church in Saratov in 1993. He subsequently quit the church, they said.

According to the police officials, the suspect contacted a friend and asked him to invite the missionaries to an apartment being specially rented in Saratov's Solnechny district, Interfax reported.

On March 19, at 8 p.m., the two American missionaries came to the apartment, where masked men surprised them with blows to the head using wooden sticks. Then, after handcuffing the missionaries, the abductors forced them into a van and drove them to an apartment, specially prepared in the suburban village of Dubki.

Then, photographs of the abducted pair were taken with a Polaroid camera and a note with a $300,000 ransom demand was scribbled. It was passed to an unwitting go-between, an acquaintance of the two young men, so that he would pass it on to the church. Church officials were warned that if they contacted police, the missionaries would be killed.

The two were reportedly hand-cuffed, blindfolded and their feet were tied while held captive.

Despite the threats, the church contacted the Russian police agency on the same day and investigation work began immediately, according to Interfax.

Boldyrev said the plotter of the abduction was in the first group of suspects. He was arrested Sunday evening in Atkarsk, a town in the Saratov region. Other reports are that a man and woman were arrested and that a third suspect is still being sought.

The arrested man described at the press conference showed where the missionaries had been captured and where they had initially been held. The Polaroid camera, a photocopying machine, a gas pistol and masks were found.

Sensing trouble, the other abductors on Sunday forced the hostages, whose eyes were bound shut with tape, into a car, drove them to the Sokur highway and dropped them off there. The missionaries returned to Saratov by themselves.

Police said the missionaries are scheduled to fly to Frankfurt, Germany, and be examined by physicians, then travel to the United States and afterward return to Saratov.