SALT LAKE CITY (AP) -- Lawyers for an environmental activist convicted of disrupting a federal oil-and-gas auction say the man has been put into isolation at a federal prison because of an unidentified congressman's complaint.
Tim DeChristopher was moved to an "isolation unit" March 9 at a federal prison in Herlong, Calif., where he gets little chance for exercise, writing or phone calls and has been let out only four times briefly in the past two weeks, his supporters at Peaceful Uprising said Wednesday.
The friends are organizing a protest in front of Salt Lake City's federal courthouse for Thursday.
The U.S. Bureau of Prisons won't confirm or deny that DeChristopher is being punished.
One of his lawyers, Pat Shea, said Wednesday that prison officials in California told DeChristopher a congressman complained about an email the 30-year-old jailed activist sent to some of his supporters. Shea said prison officials moved DeChristopher to a special section of the prison pending an investigation.
"There's no timeline for the investigation to start or end. He's being kept mostly in 24-hour lockdown. My worry is they're trying to drive him nuts," said Shea, who was able to visit DeChristopher on Sunday.
DeChristopher sent an email on an account monitored by prison officials that was wrongly "perceived as a threat" and prompted the investigation, Shea said.
Prison officials haven't publicly discussed any of DeChristopher's emails and it wasn't possible Wednesday to know the nature of any of the messages for certain. Shea and others, however, said DeChristopher was asking supporters to return a contribution from a major donor to his legal defense fund.
DeChristopher objected that the contributor moved some manufacturing operations overseas, Shea said.
"We have no idea why this would bother a congressman or how he got the email," Peaceful Uprising organizer Henia Belalia said Wednesday. "It doesn't make any sense to us. The donor is in no way related to any congress people."
Neither Shea nor DeChristopher's supporters would identify the donor. Shea said the man has contributed a total of $25,000 to the defense fund.
Bureau of Prisons spokesman Chris Burke said Wednesday that the agency won't discuss any inmate's disciplinary status. Speaking generally, Burke said an inmate can get in trouble for an email, and that anyone — "whether it's a congressman or whatever" — who feels threatened over an inmate's correspondence can file a complaint.
DeChristopher was sentenced in July to serve two years for bidding on drilling leases near Utah's national parks in an effort to keep the leases from being developed.
"My intent both at the time of the auction and now was to expose, embarrass and hold accountable the oil and gas industry, to the point that it cut into their $100 billion profits," DeChristopher said at his sentencing.
He was a University of Utah economics student when he attended the Bureau of Land Management lease auction in December 2008.
His bidding cost angry oil men hundreds of thousands of dollars in higher bids for their parcels, and DeChristopher ended up with $1.7 million in leases for which he couldn't pay. He later offered to cover it with an Internet fundraising campaign, but the government refused to accept any of the money after the fact.
DeChristopher has said the administration of former President George W. Bush violated environmental laws in holding the auction. A federal judge later blocked many of his leases from being issued and they remain off the market.
DeChristopher's lawyers will argue May 10 at the 10th Circuit U.S. Court of Appeals in Denver that the Salt Lake City federal trial judge should have let DeChristopher testify about his environmental motives. The lawyers are seeking to overturn the activist's conviction for that omission.