Whoever is targeting pro-gun control politicians with ricin-tainted letters apparently included Barack Obama on their list of threats. NBC and ABC News are reporting that an intercepted letter addressed to the president has tested positive for ricin, the second time in less than two months that such a threat has been directed at the White House. None of the letters actually reached the White House.

According to NBC News, the text of the letter was identical to those sent earlier this week to New York Mayor Michael Bloomberg and the director of his advocacy group, Mayors Agaisnt Illegal Guns. One of the threats contained in the letters stated "what's in this letter is nothing compared to what I've got planned for you." The first two were postmarked from the same post office in Louisiana.

The letters all referenced debates on gun laws and obviously appear to be targeting those who are pushing for stricter gun control. The Secret Service confirmed that the letter was intercepted and turned over to the FBI, but they have not yet revealed any information about possible suspects.

Update, 4:18 p.m.: ABC News' Aaron Katersky tweeted a photo of the letter sent to Mayor Bloomberg.