The Secret Service on Wednesday announced they intercepted a suspicious letter sent to President Obama on the same day a letter containing the poison ricin was mailed to a Republican lawmaker.

The letter sent to Obama also tested positive in preliminary tests for ricin, the FBI said on Wednesday.

The president’s protective unit said the letter was received at an off-site screening facility.

“The Secret Service White House mail screening facility is a remote facility, not located near the White House complex, that all White House mail goes through,” Secret Service spokesman Ed Donovan said. “The Secret Service is working closely with the U.S. Capitol Police and the FBI in this investigation.”

Similarly, authorities had already intercepted a letter intended for Sen. Roger Wicker, R-Miss., which tested positive for ricin.