Letter with Suspicious Substance Sent to President

WASHINGTON (AP) — The U.S. Secret Service says it has intercepted a letter addressed to President Barack Obama that contained a "suspicious substance."

Secret Service spokesman Ed Donovan says the letter was intercepted at a facility away from the White House. He says the letter was received Tuesday.

The letter comes a day after lawmakers said a letter was mailed to Sen. Roger Wicker that tested positive for poisonous ricin. Another senator said police have a suspect in mind.

Tensions have been high in Washington and across the country since the deadly bombings on Monday at the Boston Marathon that killed three people and injured more than 170.

Meanwhile

WASHINGTON (AP) — Law enforcement officials say a second letter sent to the U.S. Senate has been intercepted and is being tested for poisonous ricin.

Two officials told The Associated Press on Wednesday that the letter was being treated in the same manner as a separate one sent to Mississippi Sen. Roger Wicker and was undergoing field tests.

The officials spoke on the condition of anonymity because the investigation is ongoing.

The letter to Wicker, a Republican, was intercepted at a Senate mail facility just outside Washington and has tested positive for ricin. Sen. Claire McCaskill has said authorities have a suspect in mind in that case, though no one has been charged.

It was not immediately clear which senator the second letter was addressed to.