Police have arrested a 23-year-old man after an alleged car-jacking in Oamaru last night

Police received a report at 6.45pm, that a man with a knife was attempting to steal vehicles near the hospital.

The offender allegedly grabbed a woman out of her vehicle, holding her at knife point, before attempting to take off in her car.

When it didn't start, police allege he stole another woman's vehicle.

He was arrested shortly after and is expected to appear in Timaru District Court today.