Jan. 15, 2011  -- A member of the core group of computer "hacktivists" who founded WikiLeaks was detained by federal agents at the Seattle airport earlier this week, in an apparent attempt by authorities to learn more about the group that exposed thousands of once-secret U.S. government documents on the internet.

Jacob Appelbaum, an American citizen in his late 20s, was questioned and searched for 30 minutes at Seattle Tacoma International Airport on Monday evening after returning from Iceland. The inventor of the Tor Project, security software that allows computer users to surf the web anonymously, Appelbaum has lent his computer security expertise to WikiLeaks founder Julian Assange. He was previously detained and searched by federal agents at Newark airport last July, and is one of five WikiLeaks volunteers whose Twitter accounts were subpoenaed by the U.S. government in December.

Appelbaum gave his account of what happened at SeaTac in a long series of Tweets starting Wednesday afternoon. Brigitta Jonsdottir, a member of Iceland's parliament and an early Wikileaks activist, confirmed the authenticity of Appelbaum's Twitter account.

"I was detained, searched, and [Customs and Border Protection agents] did attempt to question me about the nature of my vacation upon landing in Seattle," posted Appelbaum.

Appelbaum wrote that the agents wanted his laptops and cell phones and "were visibly unhappy when they discovered nothing of the sort."

"I did, however," wrote Appelbaum, "have a few USB thumb drives with a copy of the Bill of Rights encoded in the block device. They were unable to copy it."

Appelbaum also claimed that he was searched without his consent, and that his request to speak to his lawyer was ignored.

Appelbaum had posted his arrival time in Seattle on his Twitter account before leaving Iceland. After he landed in Seattle, according to Appelbaum, a CBP mentioned the pre-flight posting to him, which he took to be an assertion that the federal authorities knew he was coming.

But Appelbaum was happier with his experience in Seattle than with what happened at Newark airport last summer. "The CBP agents in Seattle were nicer than the ones in Newark," Appelbaum posted on his feed. "None of them implied I would be raped in prison for the rest of my life this time."

Appelbaum Detained In Newark

Appelbaum was detained for several hours at Newark Liberty Airport on July 29, 2010 after arriving from the Netherlands. He was questioned by CBP agents and had his electronic devices, including his computer and cell phones, searched. His phones were confiscated, and customs agents made mirror images of his computer data drive in an effort to search his files.

Officials from Homeland Security and Customs and Border Patrol did not return calls seeking comment.

The searches and subpoenas for information come as the Justice Department looks for ways to prosecute Julian Assange and WikiLeaks for posting a series of classified military documents about the wars in Iraq and Afghanistan, and most recently roughly 250,000 classified State Department cables. Army private first class Bradley Manning has been accused by the military of leaking classified materials to Assange and WikiLeaks. He is currently being held in a military brig in Quantico, Virginia.

Appelbaum had earlier written on his Twitter feed that his account information had been subpoenaed by the U.S. government and warned his followers not to write him private messages on Twitter for fear that they too could be later read by Justice department prosecutors. Jonsdottir was among the WikiLeaks volunteers who received letters from Twitter informing them of U.S. subpoenas.

A lawyer for Julian Assange, Mark Stephens, told Bloomberg News that the Justice Department also requested user information about Assange, Appelbaum, Jonsdottir and two other activists from Google, Facebook and Skype.

Via Twitter, Appelbaum said that he thought that making his versions of Monday's events public might make matters worse for him, but said, "I refuse to be silent about state-sponsored ... harassment."

He also said he expecting to be meeting with CBP agents at SeaTac again soon. "I'm flying to Toronto, Canada for work on Sunday, and back through Seattle again a few days later," he tweeted. "Should be a joy to meet these guys again."

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