Britney Spears was believed to be under the influence of a cocktail of drugs and alcohol during her DUI arrest on Wednesday night.

Officers detained the Princess of Pop on suspicion of driving under the influence of a combination of alcohol and drugs around 9:28 p.m. local time, the California Highway Patrol told Page Six Thursday.

We’re told she was pulled over after allegedly driving her black BMW “erratically at a high rate of speed” while near the Borchard Road off-ramp in Newbury Park.

Spears, 44, underwent a series of field sobriety tests before she was ultimately arrested and booked into the Ventura County Main Jail.

Her chemical test results are still pending, and the investigation is still ongoing.

Additionally, an insider close to the Grammy winner told Page Six that officers also found an unknown substance inside her car at the time of her arrest.

Shortly after Spears was cuffed, she was reportedly taken to a hospital to undergo a blood draw to determine her blood alcohol content.

The “Gimme More” singer was booked at 3:02 a.m. and released at 6:07 a.m. early Thursday, per the Ventura County Sheriff’s office.

Her arraignment date is scheduled for May 4.

The “Toxic” songstress’s rep, Cade Hudson, referred to the arrest as “unfortunate” and “completely inexcusable” in a statement to Page Six.

“Britney is going to take the right steps and comply with the law and hopefully this can be the first step in long overdue change that needs to occur in Britney’s life,” he said.

“Hopefully, she can get the help and support she needs during this difficult time.”

Additionally, Hudson shared that Spears would be “spending time” with her sons, Sean Preston and Jayden James, adding, “Her loved ones are going to come up with an overdue needed plan to set her up for success for well being.”

Another source also told Page Six that the pop star was “incredibly emotional” during her arrest and didn’t want to let anyone down.

Spears’ recent run-in with the law comes after she was spotted driving erratically during a night out in October.