(CNN) -- Illinois senator and Democratic presidential candidate Barack Obama has been placed under the protection of the U.S. Secret Service, the Secret Service said Thursday. A statement from Homeland Security Secretary Michael Chertoff said he authorized the protection detail for Obama. "As a matter of procedure, we will not release any details of the deliberations or assessments that led to protection being initiated," the statement said. "For security reasons we will not release the timing, scope or details of any protective operations." The Secret Service told CNN no specific threat had been made against Obama. The Kid Rasta 8)