Geoff Brumfiel

The type of nerve agent used to poison a former Russian spy and his daughter in the U.K. was developed in a top-secret laboratory in Moscow and was once a closely held secret of the Russian government.

Sergei Skripal and his daughter, Yulia, were found slumped on a bench in the city of Salisbury on March 4. Experts quickly assessed that Skripal — a former Russian intelligence official accused of spying for the British — had been poisoned with a nerve agent.

On Monday, British Prime Minister Theresa May named the agent in a speech before Parliament.

As the news broke of a school shooting in Parkland, Fla., on Wednesday, hundreds of Twitter accounts believed to be under Russian sway pivoted.

Many had been tweeting about places like Syria and Ukraine — countries where Russia is seeking to strengthen its influence. Suddenly the accounts shifted to hashtags like #guncontrol, #guncontrolnow and #gunreformnow. Tweets mentioning Nikolas Cruz, the name of the shooting suspect, spiked.

The Trump administration released a report on the state of America's nuclear weaponry on Friday. The assessment, known as a Nuclear Posture Review, mainly concerns U.S. nukes and missiles.

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