New details emerged Friday about a threatening letter — and deadly poison — mailed to the Hidalgo County Sheriff's Office in September.

Pascale Cecile Veronique Ferrier, a woman from Canada, mailed a letter to the Hidalgo County Sheriff's Office in September, according to federal court records. The letter contained ricin, a deadly poison.

Prosecutors filed a photo of the letter in court Friday, when they asked a federal judge to keep Ferrier in jail while the case is pending.

The letter, which is addressed to a corporal at the Sheriff's Office, reads:

"Hello

"As a member of tyrants gang, you work for a dictatorship. Then the best way to eliminate tyrants is to kill them.

"So I made a 'special gift' for you, which is in this letter.

"if it doesn't work, I will find a better recipe for another poison, or I might use my gun when I'll be able to come.

"Enjoy!

"Free Rebel Spirit."

Ferrier mailed seven other letters to law enforcement officials in Texas and an eighth letter to President Donald J. Trump.

Ferrier is charged threatening to kill the president of the United States, which is a federal crime.

Court records don't list an attorney for Ferrier, who remains in federal custody and couldn't be reached for comment.

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