Focus of Boston Marathon bomb shifted to plot

BOSTON — The focus of the FBI's investigation of the Boston Marathon bombings has shifted from identification and apprehension of suspects to piecing together details of the deadly plot.

Agents are trying to determine how long the planning took, how the plot was carried out and whether anyone else knew or was involved.

A federal law enforcement official not authorized to speak on the record about the investigation told The Associated Press on the condition of anonymity Friday the FBI is gathering evidence regarding "everything imaginable."

Two bombs exploded April 15 near the marathon's finish line, killing three people and wounding more than 260.

Bombing suspect Dzhohkar Tsarnaev (joh-HAHR' tsahr-NEYE'-ehv) has been moved from a hospital to a federal prison medical center. His brother died after a shootout. Their mother says allegations against them are lies.

Tsarnaev, 19, was taken from Beth Israel Deaconess Medical Center, where he was recovering from a throat wound and other injuries suffered during an attempt to elude police last week, and was transferred to the Federal Medical Center Devens, about 40 miles from Boston, the U.S. Marshals Service said. The facility, at a former Army base, treats federal prisoners.

"It's where he should be; he doesn't need to be here anymore," said Beth Israel patient Linda Zamansky, who thought his absence could reduce stress on bombing victims who have been recovering at the hospital under tight security.