After serving only three full days behind bars, Paris Hilton was released from jail early Thursday, partly due to "medical" reasons — but she has been fitted with an electronic monitoring ankle bracelet and must remain confined to her Hollywood Hills home for 40 days.

"I can't specifically talk about the medical situation other than to say that, yes, it played a part in this," sheriff's spokesman Steve Whitmore said at a press conference Thursday morning, adding that her electronic monitoring device has a range of 3,000 feet to 4,000 feet.

Hilton's home measures 2,700 square feet, with four bedrooms and three bathrooms.

Sources close to the Hilton family told "Entertainment Tonight" that the medical reason was a rash she developed on her body.

According to People magazine, Hilton was having trouble behind bars.

"She cries all day," a source told the publication. "She looks unwashed, she has no makeup and her hair is tangled. She cried audibly through the first two nights."

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Hilton, 26, was originally sentenced to 45 days in jail for violating probation in an alcohol-related reckless driving case, but had been expected to serve 23 days because of state rules allowing shorter sentences for good behavior.

Whitmore said under the new agreement, Hilton would be confined to her home for 40 days.

"Because she has agreed to this through her attorney, her sentence is now back up to the 45 days. She has served already five days so that's 40 days," he explained, including the time she served on Sunday night and Thursday as "days" spent at the Century Regional Detention Facility in suburban Los Angeles. Hilton left the jail at 2 a.m. on Thursday.

On the heels of reports that Hilton had been crying in jail and receiving visits from her psychiatrist, reporters at the press conference seemed to think that the heiress had manipulated her jailers.

Whitmore didn't fully deny this accusation. When one reporter asked him, “What’s your comment to people who say she played you like a puppet on a string — she came in here, didn’t like it, it was hard and she got out?” he replied, “Once again, I just think that’s a different way of saying it, only the language is a little more — liquid. I would simply say that I understand that."

The sheriff's spokesman would not elaborate on Hilton's medical issues, nor would he say if they were physical or psychological. He added that the decision to send Hilton home was based on dozens of consultations and discussions over a period of three or four days.

The decision to release Hilton was made by Sheriff Lee Baca, according to the Probation Department.

When she was sentenced May 4, Superior Court Judge Michael T. Sauer ruled that she would not be allowed any work release, furloughs or use of an alternative jail or electronic monitoring in lieu of jail.

Whitmore said Thursday that Sauer "was consulted and he was advised" about her early release.

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Jared Shapiro, senior news and entertainment director of Life & Style Weekly magazine, said people aren't going to be happy about Hilton's early release.

"This is one of the most privileged, entitled people to ever walk the face of the earth, and no matter what she does — whether its a sex tape or whether she's driving drunk or whether she goes to jail — she comes out on top, she makes money off it, she profits from it and she comes out quite all right," he told FOX News.

On "The View" Thursday, co-host Elisabeth Hasselbeck said it's "disgusting" that Hilton has been transferred from jail to her home for medical reasons.

Hasselbeck said this sends a message that "if you're rich and you're hot" then "we'll let you off the hook."

Even the audience sounded horrified when Barbara Walters announced the news about Hilton.

But the comedian of the group, Joy Behar, took a lighter view. She said Hilton is her new idol because she can "get out of more things than David Copperfield."

The hotel heiress surrendered to authorities with little fanfare Sunday night after a surprise appearance earlier that day at the MTV Movie Awards, where she worked the red carpet in a strapless designer gown.

"I am trying to be strong right now," she told reporters at the time. "I'm ready to face my sentence. Even though this is a really hard time, I have my family, my friends and my fans to support me, and that's really helpful."

After she checked in, Whitmore said Hilton's demeanor was helpful.

"She was focused; she was cooperative," he said.

Hilton's lawyer, Richard Hutton, said Monday after his client's first night in jail that she was doing well under the circumstances.

"She's using this time to reflect on her life, to see what she can do to make the world better and hopefully, in my opinion, to change the attitudes that exist about her among many people," Hutton said after visiting Hilton.

Hilton was housed in the "special needs" unit of the 13-year-old jail, separate from most of its 2,200 inmates. The unit contains 12 two-person cells reserved for police officers, public officials, celebrities and other high-profile inmates. She didn't have a cellmate.

The 13-year-old jail, a two-story concrete building next to train tracks and beneath a bustling freeway, has been an all-female facility since March 2006. It's located in an industrial area about 12 miles southeast of downtown Los Angeles.

Hilton was spending 23 hours a day in her cell, her lawyer said. Like other inmates in the special-needs area, Hilton took meals in her cell and was allowed outside for at least an hour each day to shower, watch TV in the day room, participate in outdoor recreation or talk on the telephone.

Officers arrested Hilton, star of "The Simple Life" reality TV show, in Hollywood on Sept. 7. In January, she pleaded no contest to the reckless-driving charge and was sentenced to 36 months' probation, alcohol education and $1,500 in fines.

She was pulled over by California Highway Patrol on Jan. 15. Officers informed Hilton she was driving on a suspended license and she signed a document acknowledging she was not to drive. She then was pulled over by sheriff's deputies on Feb. 27, at which time she was charged with violating probation.

Kyle Richards, an aunt of Hilton's, said earlier that Hilton was doing well but was bored in jail.

"She's just sitting in there for 23 hours a day with nothing to do," she said. "She picked out a bunch of books to take with her, but at the last minute she found out they wouldn't let her take the books. They wouldn't let her take anything."

The Associated Press and the New York Post contributed to this report.

Click here for FOXNews.com's Paris Hilton center.

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