Simplify the following text for a Grade 8 native English-speaking person.
Original: Between May and September of 1991 Chandler worked as an informant for the US customs Tampa office , at the same time as Tampa police investigated the Rogers family triple murder .
Simplified: Between May and September of 1991 , Chandler worked as an informant for the U.S. Customs Tampa office , at the same time that Tampa police investigated the Rogers family triple murder .