Maj. Nidal Malik Hasan, a former Army psychiatrist, will be shot to death on Dec. 3 at Fort Hood, where he killed 13 and wounded 32 in 2009.

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A yearslong investigation led federal agents to arrest an 18-year-old in Minnesota this week after he purchased a rifle from an undercover officer.

© Adam Bettcher/Associated Press

The country was shaken after nearly 30 people were killed in two separate mass shootings. South Africans are demanding greater government intervention.

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