According to the L.A. County Sheriff’s Dept., 21-year-old Lohan was nailed around 2:15 AM near Pico Boulevard and Main Street early Tuesday morning.

Lindsay Lohan was popped for possession of cocaine, driving under the influence, transporting a narcotic into a custodial facility and driving on a suspended license. Sources say her blood alcohol level was between .12 and .13, well over the .08 legal limit.

Cops tell TMZ cocaine was found in her pants pocket [during a search at the station].

If convicted, she would almost certainly do time, especially with another possible DUI looming.

Law enforcement now says Lohan was stopped after cops got a call of a vehicle being chased by another vehicle. The chasing vehicle was being driven by Lohan.

Lohan was driving a white Denali. She was chasing a Cadillac Escalade.

Lindsay Lohan is out of jail.

Law enforcement sources say Lohan was cooperative in jail. We’re told she was very upset.

A law enforcement source at the Santa Monica jail tells TMZ "she did just about everything we asked."

…[except] She refused to submit to a PASD — Preliminary Alcohol Screening Device. That’s a chemical test administered in the field to determine blood alcohol levels.

We’re told cops did administer a walk-the-line test, and Lindsay flunked.

The sophisticated SCRAM alcohol monitoring device which Lindsay Lohan voluntarily strapped around her leg wasn’t the reason cops busted her for DUI Thursday morning.

TMZ contacted a rep from the company that monitors the SCRAM bracelet who said, "I didn’t even know she was arrested."

“I have saved and saved, and I don’t have to work another day. When I won Idol and started working with a business manager, she asked, ‘What do you want?’ I was like, I don’t ever want to have to make a decision because I need money. So we accomplished that two years ago, and I’m set.”