According to U.S. immigration officials, a woman was arrested on suspicion of sending a package of castor oil poison to U.S. President Donald Trump.
The nameless woman was found at a border crossing in Buffalo, New York, while attempting to enter the United States from Canada and was reportedly in position of a gun.
The letter containing the deadly poison is believed by investigators there to have been sent from Canada.
The letter was found last week before it got to the White House.
Castor oil, a poison naturally found in castor beans, has been used in other attempts to attack the White House in recent years.
The Trump administration has not yet commented on the reports.
The Federal Bureau of Investigation (FBI) and the Secret Service are investigating the package that was discovered in a mail processing plant that was sent to the White House.
“At this time, no threat to public safety is known,” the FBI said on Saturday.
The suspect may also have sent ricin to addresses in Texas, including a prison and a sheriff’s office.
The presence of ricin was confirmed after several tests conducted by the FBI, officials said.
The Royal Canadian Mounted Police (RCMP) said on Saturday it was working with the FBI to investigate the “suspicious letter to the White House.
Ricin is a deadly substance that can cause nausea, vomiting, internal bleeding and eventually organ failure if ingested, inhaled or injected.
There is no known antidote to ricin. If a person is exposed to ricin, death can occur within 36 to 72 hours depending on the dose received, according to the U.S. Centers for Disease Control and Prevention (CDC).
The CDC said the poison used in terrorist plans can be made into a weapon in the form of gunpowder, mist or pellets.
The White House and other federal buildings have been the target of castor bean packages in the past.
In 2014, a Mississippi man was sentenced to 25 years in prison for sending castor oil letters to former President Barack Obama and other officials.
Four years later, in 2018, a former Navy veteran was accused of sending poisonous letters to the Pentagon and the White House.