When you are 19 and have a flat stomach, why not flaunt it?

Selena Gomez showed off her slender frame in a sheer midriff top while running errands in California over the weekend.

The singer and actress was spotted filling up her car at a petrol station in her revealing top which displayed her skinny waist.

Racy in lace: Selena Gomez fills up her car with petrol in a midriff-baring lace top

The teen star wore grey skinny jeans and sandals and accessorised with large silver hoop earrings.

Selena chatted on her phone as she filled up her car, ignoring the various warning signs that advised of the dangers of mobile phone use.

Miss Gomez also washed the windscreen of her Cadillac Escalade.

Naughty: The actress used her mobile phone despite signs advising of the dangers

Clear vision: Selena cleaned her windscreen as well

The following day, Selena was caught up in an altercation with the paparazzi which saw her boyfriend Justin Bieber lose his cool.

Selena was spotted trying to calm the singer down after the incident.

The Wizards of Waverley Place star was pictured attempting to soothe Justin by stroking his arm and helping to collect his hat and shoes, which flew off during the altercation.

Skinny genes: The former Disney princess slipped her slender frame into grey skinny jeans

Bieber is now reported to be wanted by the police for questioning.

The photographer reported the star to the Los Angeles County Sheriff, claiming Bieber ‘roughed him up’.

But Selena and Justin left the scene before police arrived, so police are now understood to be keen to speak to them to hear their side of the story.

Level-headed: The next day Selena had to calm down boyfriend Justin Bieber when he lost his cool with the paparazzi