Aerial view of the Pentagon. Photo: Bill Clark/CQ Roll Call

An initial test detected ricin on packages addressed to Defense Secretary James Mattis and Admiral John Richardson, the chief of naval operations, during a screening at the Pentagon's mail facility Monday, according to CNN.

The details: The remote mail facility is in a separate building on the Pentagon's grounds, and the envelopes that tested positive did not enter the Pentagon itself. Ricin is a poisonous substance found naturally in castor beans, according to the CDC. If ingested, the substance can cause fever, cough, difficulty breathing, nausea and tightness in the chest.

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As boycott grows, Facebook juggles rights groups and advertisers

Illustration: Aïda Amer/Axios

As an advertiser boycott of Facebook over its tolerance of hate speech continues to snowball, the company has begun making small, incremental changes to mollify activists while it tries to buy time to evolve its content policies.

Driving the news: Sources tell Axios that the product and policy changes sought by the #StopHateForProfit campaign were long under discussion both inside Facebook and with some external groups. Meanwhile, CEO Mark Zuckerberg has reportedly told employees that the boycotting advertisers will be back before long.

Replacing the nursing home

Illustration: Sarah Grillo/Axios

Nursing homes have been the epicenter of the coronavirus outbreak, prompting more urgent discussions about alternative housing situations for elderly Americans.

Why it matters: Deaths in nursing homes and residential care facilities account for 45% of COVID-19 related deaths, per the Foundation for Research on Equal Opportunity — but there are few other viable housing options for seniors.

3 hours ago - Health

How Joe Biden would tackle the coronavirus

Illustration: Aïda Amer/Axios

If Joe Biden wins in November, his coronavirus response would feature a no-expenses-spared federal approach to mitigating the virus and a beefed-up safety net for those suffering its economic consequences.

Why it matters: It’s nearly inevitable that the U.S. will still be dealing with the pandemic come January 2021, meaning voters in America will choose between two very different options for dealing with it.