Man arrested for stabbing 15-year-old

A man accused of stabbing a teenager during an argument in Sydney's northwest will remain behind bars into the new year.

Police say the 15-year-old boy was with a group of friends at Emerton on Sunday night when they became involved in an argument with a group of men.

During the argument the teen was allegedly stabbed by a man who then ran away.

The boy was taken to Westmead Hospital in a serious condition.

Police later arrested a 21-year-old man at Parramatta railway station about lunchtime on Tuesday.

He was charged with malicious wounding and was refused bail when he appeared at Parramatta Local Court on Wednesday.

He is due to re-appear at Penrith Local Court on January 9.

Police say their investigation into the stabbing is continuing and ask for anyone with information to come forward.