WASHINGTON — A four-year federal investigation led to the arrest of Prince George’s County Executive Jack Johnson Friday, Nov. 12. Three days later, FBI agents arrested nine people, including three county police officers, for conspiracy to commit extortion and traffic drugs.

Check out our timeline of the complete events. Put your cursor over each of the black dots to see each incident, or click on them for details. You can also use the white buttons at the bottom to narrow or broaden the time frame.

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