The video obtained by celebrity website TMZ.com was said to have been shot days after Cyrus turned 18 in November. It shows the Disney Channel "Hannah Montana" star giggling and laughing after smoking from a large glass pipe, commonly called a bong. TMZ said sources close to Cyrus told the celebrity news website that the video was shot by one of Cyrus's friends but the substance was not marijuana, which is typically smoked in bongs.

"Is that me tripping!?", Cyrus exclaims in the video, after using the bong and mistaking another person at the party for her ex-boyfriend, actor Liam Hemsworth. The herb salvia divinorum has hallucinogenic properties but is not illegal in California. According to a 2007 US survey on drug use and health, about one million people had used it that year. The video made headlines around the world and even caused one betting site, bookmaker.com, to place odds on what might next be revealed about Cyrus. Examples included whether she might attend rehab, or be dropped by her record label.

Cyrus, one of the world's best-known teen celebrities, has made strenuous efforts this year to distance herself from the "Hannah Montana" character she began portraying on Disney Channel four years ago, winning millions of young fans.

After taping the last season of "Hannah Montana", she played a rebellious and sullen teen in romantic movie "The Last Song", stepped out publicly with co-star and boyfriend Hemsworth, released a series of raunchy pop music videos, and adopted figure-hugging stage outfits.