OXFORD, Miss. — Investigators haven't found any ricin in the
house of a Mississippi man accused of mailing poisoned letters
to President Barack Obama, a U.S. senator and a local judge,
according to testimony Monday from an FBI agent.  Agent Brandon
Grant said that a search of Paul Kevin Curtis' vehicle and house
in Corinth, Miss., on Friday did not turn up ricin, ingredients
for the poison, or devices used to make it. A search of Curtis'
computers has found no evidence so far that he researched making
ricin.  Defense lawyers for Curtis say investigators' failure to
find any ricin means the government should release their client.
That lack of physical evidence could loom large as a detention
and preliminary hearing continues Tuesday morning.   Still,
Grant testified that authorities believe that they have the
right suspect.  He testified that there were indentations on the
letters which, when analyzed under a light source, turned out to
be for Curtis' former addresses in Booneville and Tupelo, though
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