Rudd said attacks like Masood's would be easier to prevent if
authorities could penetrate encrypted services after obtaining a warrant
similar to the ones used to listen in on telephone calls or - in snail
mail days - steam open letters and read their contents.
British police investigating the attack say they still believe Masood, a
52-year-old Briton, acted alone and say they have no indications that
further attacks are planned.
Deputy Assistant Commissioner Neil Basu said it may never be possible to
fully determine Masood's motives.
"That understanding may have died with him," Basu said Saturday night as
police appealed for people who knew Masood or saw him to contact
investigators. "Even if he acted alone in the preparation, we need to
establish with absolute clarity why he did these unspeakable acts, to
bring reassurance to Londoners."