The Elvis impersonator who was charged with allegedly sending letters to the White House that contained ricin will remain in custody until April 29 when a grand jury will expectantly indict him.

During a four-minute hearing, Magistrate Judge S. Allan Alexander ordered the alleged ricin sender, Paul Kevin Curtis to remain in custody until a grand jury issues an expected indictment and a preliminary and detention hearing on April 29, according to CNN.   

One of the letters was allegedly intending for President Barack Obama. Curtis' attorney, Christi McCoy, told CNN in an e-mail that "Mr. Curtis vehemently denies the allegations against him."

A criminal complaint charged Curtis with "knowingly depositing for conveyance in the mail and for delivery from any post office any letter, paper, writing or document containing threats to take the life of or to inflict bodily harm upon the President of the United States."

According to the department, all three letters were typed on yellow paper and read as follows:

"No one wanted to listen to me before.

There are still 'Missing Pieces'

Maybe I have your attention now

Even if that means someone must die.

This must stop.

To see a wrong and not expose it,

is to become a silent partner to its continuance

I am KC and I approve this message"

In confirming the letters tested positive for ricin, the FBI said it was "not aware of any illness as a result of exposure to these letters."

These letters had no return address, but were intercepted by the U.S. Senate before reaching the White House.

Ricin is a protein that is a lethal toxic. A dose the size of a few grains of table salt can kill an adult human. Following the 9/11 attacks of the World Trade Center, letters with anthrax were sent out as a way to poison and kill people. 

If convicted, Curtis will face a maximum of 15 years in prison, $500,000 in fines and three years of supervised release.

One of these ricin-letter were allegedly intending for Sen. Roger Wicker of Miss.

Wicker said Thursday that he met Curtis about a decade ago. "He's an entertainer," the senator said. "He's an Elvis impersonator, and he entertained at a party that my wife and I helped give for a young couple that was getting married. He was quite entertaining."