(CNN) — An arrest has been made in connection with letters sent to President Barack Obama and Sen. Roger Wicker that authorities are testing to determine if they contain ricin, two federal law enforcement officials said Wednesday.
The person was arrested in the Tupelo, Mississippi area, one of the officials said.
Discovered Tuesday, the letters were addressed to Obama and to Wicker, R-Mississippi.
The letters were stopped at a government mail-screening facility after initial tests indicated the presence of ricin.
Because initial tests can be “inconsistent,” the envelopes have been sent off for additional tests, an FBI statement said. The FBI does not expect to receive results from the tests until Thursday, federal law enforcement sources told CNN.
CNN’s Jessica Yellin, Dana Bash, Tom Cohen, Terry Frieden, Deanna Hackney, Elwyn Lopez, Lisa Desjardins and Rachel Streitfeld contributed to this report.