Los Angeles, Sep 25 (IANS) Troubled actress Lindsay Lohan was sent to jail again a week after she admitted that she failed a drug test ordered by the court.

Los Angeles county sheriff's spokesman Steve Whitmore told reporters Lindsay will be housed in "administrative segregation" because of her celebrity status for her safety and the safety of the jail system.

He also said the only way she could be released before her probation hearing Oct 22 is if the judge issues another order, tmz.com reported.

The "Mean Girls" star was in court because she failed two drug tests -- in one she tested positive for cocaine and the other for Adderall.

Judge Fox did not hear any arguments from the lawyers before making his ruling.

"It's shocking because the underlying offence is a misdemeanour, and people connected with the case were telling us the judge had to offer Lindsay bail, Lindsay's lawyer, Shawn Chapman Holley was quoted as saying.

Lohan confirmed in a Twitter posting last week that she had failed a court-ordered drug test. The random tests Lohan is subjected to twice a week are part of her punishment from her time behind bars and in rehabilitation.

Lohan spent three weeks at a drug-rehabilitation programme last month. She went into the rehab programme after serving 13 days in jail for violating her probation.

After her release from the rehabilitation programme, Fox ordered Lohan to remain in Los Angeles, participate in psychotherapy counselling and chemical dependency sessions, in addition to 12-step meetings. She was also ordered to submit to random drug and alcohol testing no less than twice a week and attend behavioural therapy classes twice a week.