NSW man breaks into retirement home: cops

A 21-year-old man has been charged after he allegedly broke into a retirement unit and threatened an 84-year-old woman in her bed on Sydney's northern beaches.

The woman woke at 3am at the Mona Vale facility on Thursday to find a man standing by her bedside after he climbed through her bedroom window.

She screamed and pressed a panic alarm and the man ran from the unit.

The woman was shaken, but unharmed by the incident.

Police later arrested a 21-year-old man nearby and charged him with aggravated entering a dwelling, with intent, knowing people there; and, having goods in custody suspected of being stolen.

The Warriewood man was refused bail and taken to Manly Hospital for assessment.