The Mississippi man suspected of sending ricin-laced letters to the White House was ordered to be held without bond until a hearing on Thursday.

A federal magistrate on Monday ruled that J. Everett Dutschke would remain in custody pending the preliminary hearing. 

Dutschke was arrested Saturday for allegedly sending the poison-filled letters to President Obama, Sen. Roger WickerRoger WickerTrump Navy secretary nominee moves forward to Senate vote 355-ship Navy not a must under Trump's secretary nominee GOP senator: 'Everybody wants to get to yes' on healthcare MORE (R-Miss.) and a local judge. 

It was the second arrest law enforcement officials have made in the case, after mistakenly arresting Paul Kevin Curtis, who officials initially believed sent the letters. Authorities eventually dropped the charges against Curtis and Curtis's lawyer suggested his client could have been framed, possibly by Dutschke.

Dutschke, who was arrested by FBI agents in Tupelo, Miss., where he lives, has denied sending the letters. 

He was charged with "knowingly developing, producing, stockpiling, transferring, acquiring, retaining and possessing a biological agent, toxin and delivery system for use as a weapon, to wit: ricin, and with attempting, threatening and conspiring to do the same," according to a statement from the U.S. attorney's office. 

If found guilty Dutschke could face life in prison.