More details have emerged about what led to singer/songwriter Bruno Mars' arrest early Sunday morning in Las Vegas on drug-possession charges.

According to a copy of the arrest document provided by the Las Vegas Metropolitan Police Department, the "Just the Way You Are" singer was arrested around 1:50 a.m. at the Hard Rock Hotel and Casino — where he had performed earlier in the night — for felony possession of 2.6 grams of a "white powdery substance" that tested positive as cocaine.

Mars (born Peter Gene Hernandez), 23, was taken in after Las Vegas police received a narcotics call from someone at the Hard Rock. According to the report, a bathroom attendant approached a security officer at the facility to say that there was a man in a bathroom stall who might be using drugs, telling the guard that a male in the bathroom was "taking a really long time."

The attendant said he observed the suspect in a striped shirt with a "baggy of white powder substance." The attendant and the security guard approached the suspect as he exited the stall, and the guard ordered Mars to hand over whatever narcotics he had on him. "This is when Hernandez, with his left hand, pulled out a white powder substance, which was consistent with cocaine, from his left-front jeans pocket."

When the guard asked Mars if he knew why he was being detained, the singer reportedly said, "Can I speak to you honestly, sir?" and then said he "did a foolish thing and has never used drugs before."

Mars was arrested when the substance tested positive for cocaine, and he was then transported to the Clark County Detention Center, where he was booked on a felony charge of possession of a controlled substance.