SANTA MONICA, Calif. – The troubled saga of Lindsay Lohan took another dangerous turn early Tuesday when police booked her on suspicion of drunken driving and cocaine possession after a frightened woman dialed 911 to report being chased by Lohan’s SUV.

Less than two weeks out of rehab, with another drunken-driving case pending, Lohan had a blood-alcohol level of between 0.12 and 0.13 percent when police found her about 1:30 a.m., Sgt. Shane Talbot said.

Lohan attorney Blair Berk said her client had relapsed and was again receiving medical care.

“Addiction is a terrible and vicious disease,” Berk said in a statement Tuesday.

Authorities had received a 911 call from the mother of Lohan’s former personal assistant, said Officer Alex Padilla. The assistant had just quit hours before, he said.

“The mother was afraid,” Padilla said. “She wasn’t quite sure what was going on so she called the police saying she wanted to make sure everything was going to be OK.”

The woman apparently didn’t realize it was Lohan who was behind her, Padilla said.

Police said the woman drove her black Cadillac Escalade into the parking lot of Santa Monica’s Civic Auditorium, about a block away from the Santa Monica Police Department, followed by Lohan driving a Denali sport utility vehicle. Authorities arrived and saw Lohan and the woman in “heated debate,” Padilla said. Lohan and the woman each had two passengers in their vehicles, Padilla said.

After a sobriety test, the 21-year-old movie star was booked on suspicion of two misdemeanor charges of driving under the influence and driving on a suspended license and two felony charges of possession of cocaine and transport of a narcotic, authorities said.

During a pre-booking search, police found cocaine in one of Lohan’s pants pockets, Talbot said.

Several hours later, Lohan was released on $25,000 bail.

Padilla said he didn’t know why Lohan was trying to catch the woman, whom he didn’t name.

Last week, Lohan turned herself in to Beverly Hills police to face charges of driving under the influence in connection with a Memorial Day weekend hit-and-run crash.

Lohan lost control of her 2005 Mercedes SL-65 convertible and crashed into a curb and shrubs on Sunset Boulevard, police said. Lohan’s blood-alcohol level at the time of that crash was above the legal limit, authorities said, but they wouldn’t disclose how high it was. She also faces a misdemeanor charge of hit and run in that case.

A court date was scheduled in that case for Aug. 24.

Lohan left Promises Malibu Alcohol and Drug Rehab Treatment Facility on July 13, after a stay of more than six weeks.

When she left, publicist Leslie Sloan Zelnik said Lohan would voluntarily wear an alcohol-monitoring bracelet.

“In part she is wearing the bracelet so there are no questions about her sobriety if she chooses to go dancing or dining in a place where alcohol is served,” Zelnik said in a statement at the time.

Padilla said he wasn’t sure if Lohan _ who had also checked into rehab for substance abuse treatment in January _ was wearing it when she was stopped early Tuesday.

Since her release, Berk said, Lohan had been tested daily in order to support her sobriety.

“Throughout this period, I have received timely and accurate reports from the testing companies,” Berk said. “Unfortunately, late yesterday I was informed that Lindsay had relapsed. The bracelet has now been removed. She is safe, out of custody and presently receiving medical care.”

Associated Press Writer Jeff Wilson contributed to this report.