Mother of Russian lab worker who died of plague: 'I know the truth'

The lab in Irkutsk, where the Russian worker died, has long been suspected of developing bioweapons, according to author Annie Jacobsen, who recently released her nonfiction book, "Biological War: A Scenario." Leigh Kiniry reports.

The death of a lab worker from a Siberian plague institute has sparked concerns around the world. The U.S. has sent a diplomatic complaint to Russia over a lack of transparency, a U.S. official says. ABC News’ Patrick Reevell breaks down what we know.

The mother of a Russian lab worker who reportedly died of the pneumonic plague has rejected claims about her death.

Svetlana Shipilova, the mother of the anti-plague institute worker who died in Russia, has reportedly spoken out following her daughter's death.