<p>FBI agents armed with search warrants raided two houses in a southwestern suburb of Philadelphia yesterday, backed by members of a hazardous-materials squad wearing full protective gear.</p>
<p>Located less than two blocks apart in Chester, Pa., some 15 miles southwest of Philadelphia, the houses are owned by Dr. Irshad Shaikh, a Pakistani physician and specialist in epidemic diseases who is Chester's city health commissioner, and by Asif Kazi, the Chester city accountant, who also is a Pakistani native.</p>
