TEXARKANA, Texas - A pregnant actress who told the FBI her husband had sent ricin-tainted letters to President Obama and New York City Mayor Michael Bloomberg, then allegedly said her husband made her mail the letters, was charged Friday with threatening the president.

Shannon Guess Richardson, 35, appeared in a Texarkana courtroom after being charged with mailing a threatening communication to the president. The federal charge carries up to 10 years in prison, U.S. Attorney's Office spokeswoman Davilyn Walston said.

Richardson, who has had bit roles in television shows, was arrested earlier Friday for allegedly mailing the ricin-laced letters last month to the White House, Bloomberg, and the mayor's Washington gun-control group. The letters threatened violence against gun-control advocates, authorities said. Her court-appointed lawyer didn't immediately return a message seeking comment.

If inhaled, ricin can cause respiratory failure, among other symptoms. If swallowed, it can shut down the liver and other organs, resulting in death.

According to an FBI affidavit, Richardson contacted authorities May 30 to implicate her husband. She later failed a polygraph test and investigators also found inconsistencies in her story, the document said. Richardson then admitted mailing the letters knowing they contained ricin, but said her husband had typed them and made her print and send them.

On Wednesday, FBI agents wearing hazardous-material suits were seen going in and out of the Richardsons' house in nearby New Boston. Officials have said the search was initiated after Shannon Richardson contacted the FBI.

No charges have been filed against her husband, Nathaniel Richardson, 33, an Army veteran. His attorney, John Delk, said the Richardsons were going through a divorce.

Delk told the Associated Press his client was pleased with his wife's arrest and was working with authorities to prove his innocence. Delk said he wasn't anticipating that his client would be arrested.

Delk said the Richardsons were expecting their first child in October. She also has five children, ages 4 to 19, from other relationships, he said.

She was seen leaving a Texarkana hospital shortly before the court hearing, though it was unclear why she was there.

Shannon Richardson's resume on the Internet movie database IMDb said she has had small television roles in The Vampire Diaries and The Walking Dead, and a minor role in the movie The Blind Side.