Less than a month after completing a stint in rehab, actress Lindsay Lohan faces more jail time.

The Machete actress, who recently served nearly two weeks in jail, admitted late last night that she has fallen back into old habits. Her confession came hours after TMZ reported that Lindsay had failed two court-ordered drug tests.

According to the site, a test taken last week reported positive for cocaine. Another test taken this week detected a different substance.

It was just this past Sunday when Lohan had joked about her troubles with Chelsea Handler on the Video Music Awards. At one point, the supposedly clean star had also been rumored for a possible hosting gig on Saturday Night Live.

Although she initially denied to Us Weekly that TMZ’s reports were true, she later acknowledged her setback through her own Twitter account.

“Regrettably, I did in fact fail my most recent drug test and if I am asked, I am prepared to appear before judge Fox next week as a result,” Linds wrote. “Substance abuse is a disease, which unfortunately doesn’t go away over night.  I am working hard to overcome it and am taking positive steps forward every day. I am testing every single day and doing what I must do to prevent any mishaps in the future.”

“This was certainly a setback for me but I am taking responsibility for my actions and I’m prepared to face the consequences,” the 24-year-old claimed. “I am so thankful for the support of my fans, loved ones and immediate family, who understand that i am trying hard, but also that I am a work in progress, just as anyone else. I am keeping my faith, and I am hopeful….Thank you all!!!”

Per the terms of her probation agreement, the infraction is punishable by 30 days of jail time. At this time, Superior Court Judge Elden Fox has not yet set a date for Lohan to appear in court.

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