A man was arrested and charged on Friday in connection with about 100 envelopes containing threatening letters and a suspicious powdery substance mailed from Oregon to members of Congress and the news media, authorities said.
A federal grand jury returned a two-count indictment charging Christopher Lee Carlson, 39, of the Portland area, with one count of mailing a threatening communication to a member of Congress and one count of mailing a letter threatening to use a biological weapon to a U.S. senator.
Carlson was arrested at his home on Friday morning, the U.S. Capitol Police said in a statement after an investigation it conducted with the FBI and U.S. Postal Inspection Service.
All the envelopes examined so far , which were postmarked in Portland and contained an unidentified white powder , have tested negative for any toxic substances, the U.S. Attorney's Office in Portland said in a statement announcing the indictment.
But both letters cited in the indictment, one sent to House of Representatives Speaker John Boehner, an Ohio Republican, and the other to Senator Barbara Mikulski, a Democrat from Maryland, contained threats to the lawmakers.
The letter to Mikulski, addressed to her Baltimore office, "indicated that it may contain a lethal pathogen to which the recipient may have been exposed," the indictment said.
"Threatening letters - whether hoax or real - are serious concerns that federal law enforcement agencies will aggressively pursue," Greg Fowler, special agent in charge of the FBI office in Oregon, said in a statement.
Neither the indictment nor the press release accompanying it made any mention of a possible motive for the mass mailings of menacing letters.
The federal prosecutor's statement said Carlson was expected to be arraigned in U.S. District Court on Monday.
The threatening letters began showing up on Capitol Hill and in the state offices of lawmakers on Feb. 22. A number of media organizations and television shows, including The New York Times, National Public Radio and "The Daily Show with Jon Stewart," also received such mail.
A law enforcement source at the time said the sender warned that letters had been sent to the Washington or local offices of all 100 U.S. senators and that 10 contained a deadly pathogen.
In 2001, in the wake of the Sept. 11 attacks on the World Trade Center and Pentagon, deadly anthrax-laced letters were sent to several news organizations and Senate offices.
Five people were killed and 17 sickened by those letters, which federal investigators said were ultimately traced to a U.S. Army scientist who committed suicide in 2008.
EU leaders agreed last week to increase sanctions against President Bashar al-Assad's regime, citing devastating attacks on Syria's second city of Aleppo.
"I strongly believe it is absolutely possible to strengthen European defence without duplicating efforts by NATO," alliance chief Jens Stoltenberg said.
12 people were killed Tuesday after al-Shabaab militants carried out attack in Mandera near Kenyan-Somali border
Head of Kurdish Regional Government says ‘only Iraqi counter-terrorism forces’ will enter Mosul once ISIL is defeated
25 militants killed in western Anbar province while another 5 are killed near Kirkuk, local military sources say
Jobless rate drops below 20 percent for first time in 6 years, despite Spain lacking agreed government for last 10 months
The airlines, owned by flag carrier Lufthansa, are locked in disputes with the Ufo flight attendants union.
Stoltenberg said NATO had just launched its own Operation Sea Guardian in the Mediterranean to help support Operation Sophia.
Belgium has effectively blocked the deal, which must be endorsed by all 28 EU member states.
No casualties reported from quake, which was felt as far away as Rome
The incident takes place Tuesday in Qalqilya, northern West bank
Consultative meetings also due next week on forming a government of reconciliation in Libya
'There are no more migrants in the camp.' says Pas-de-Calais prefect Fabienne Buccio
At least 3,800 people have died, making 2016 the deadliest ever, says UNHCR spokesman
In Kenya, Rockefeller Foundation panel says 1/3 of food never makes if from farm to table
Iraqi army, meanwhile, captures strategic oilfield northeast of ISIL-held city