A Pentagon spokesman says authorities found at least two packages suspected of containing ricin, a poison made from castor beans.

One of the envelopes was reportedly addressed to Defense Secretary James Mattis.

Two packages containing a suspicious substance are being tested by the FBI, officials say.

At least two envelopes at a Department of Defense mail processing center were suspected to contain the deadly toxin ricin, a Pentagon spokesperson said Tuesday.

Pentagon police referred the matter to the FBI, who did not immediately return a request for comment.

Two pieces of mail that arrived at a Pentagon distribution center have tested positive for the poison ricin, defense officials said.

Two pieces of mail that arrived at a Pentagon distribution center have tested positive for the poison ricin, defense officials said.

Two pieces of mail that arrived at a Pentagon distribution center have tested positive for the poison ricin and a “suspicious envelope” had been sent to the White House, defense officials and the Secret Service said.

Two pieces of mail that arrived at a Pentagon distribution center have tested positive for the poison ricin, defense officials said.

Two pieces of mail that arrived at a Pentagon distribution center have tested positive for the poison ricin, defense officials said.

A piece of mail delivered to the Pentagon mail facility has initially tested positive for ricin, according to two US defense officials.

The envelopes did not enter the Pentagon itself.

The US Secret Service says it's investigating a suspicious envelope addressed to President Donald Trump. The development comes after reports that another suspicious piece of mail, reportedly containing the deadly poison ricin, was sent to Penatgon officials o…

Mail delivered to the Pentagon has tested positive for Ricin, a potentially deadly poison, according to a report from CNN based on discussions with US defense officials.

RT @esportspartizan: @breaking_frames Kid named Ricin https://t.co/wZV8D3gtu8

RT @mfisrae: @breaking_frames the ricin: https://t.co/urYTPCGqdM

Nice to meet you. I'm Natasha, an underworld doctor. Feeling sick? Like you've got the flu? That would be the ricin I gave you. I slipped it into that stevia crap that you're always putting in your tea. Well... Goodbye, Lydia. https://t.co/v6Htj2ONVH

RT @CBaguetto: "We could make such a pretty picture" going back to my poster-art style because bright colors tickle my brain in the right…

RT @esportspartizan: @breaking_frames Kid named Ricin https://t.co/wZV8D3gtu8

RT @mfisrae: @breaking_frames the ricin: https://t.co/urYTPCGqdM

RT @jay_da_tooth: @breaking_frames the ricin: https://t.co/zV7jGkGmlR

RT @esportspartizan: @breaking_frames Kid named Ricin https://t.co/wZV8D3gtu8

Ricin came in clutch https://t.co/pz8lxd9hNq https://t.co/MXGYkqaG02

RT @mfisrae: @breaking_frames the ricin: https://t.co/urYTPCGqdM

RT @JaadXxV: @breaking_frames The ricin in lydia's nervous system https://t.co/3mc7L9JoOG

RT @ROCKET_888: @breaking_frames The ricin in her bloodstream https://t.co/3LmjSlDDcP

RT @mfisrae: @breaking_frames the ricin: https://t.co/urYTPCGqdM

RT @esportspartizan: @breaking_frames Kid named Ricin https://t.co/wZV8D3gtu8

A White Powder found in The West Wing of The White House with zero consequences. May as well been Ricin or Anthrax!!!

RT @gnocchislayer: @MEB_Justice Think about that…thankfully it was not radioactive, ricin, or anthrax. They know exactly who it was…

RT @IamBrookJackson: RiVax - Ricin Toxin Vaccine show positive protection here: https://t.co/WmgQNd87Xd Other U.S. Medical Countermeasures…

RT @MyLifeFlashed: I wonder how the @SecretService would’ve reacted to the white powder being Ricin?

I wonder how the @SecretService would’ve reacted to the white powder being Ricin?

Cocaine being found in the WH is a national security issue (sub in ricin for the cocaine). The fact that the Secret Service doesn’t think so, tells everyone that they know who it is. And, that person is being protected.

Yeah….Just a tourist, (terrorist) dropping off their cocaine (anthrax, sarin, ricin) in the White House….. Yeah…That’s what happened. Now we know why she’s a FORMER Secret Service Agent. (Stooge) https://t.co/MHEnn8M0Em

Shame how these agencies' operating budgets are in the billions and they are so inept that between them all, they "can't find" who placed a bag of cocaine in the White House. COULD HAVE BEEN RICIN!