Paris Hilton's brother has pleaded guilty to simple assault following a meltdown on a plane last summer (Jul14).

Conrad Hilton, 20, allegedly threatened to "f**king own anyone on this flight", and he has accepted a plea agreement in court and now faces a maximum sentence of six months behind bars followed by a year of supervised release and a fine of $5,000 (Gbp3,300), according to

Hilton had to be handcuffed to his seat on the flight after taking a sleeping pill which caused his unruly behaviour.

He was arrested on 3 February (15) and has since voluntarily checked himself into a rehab facility.