A fire caused up to $100,000 of damage to an unoccupied Kenthurst house on Friday.
The fire, that started about 12.20pm, had engulfed most of the first storey of the Park Road house by the time brigades arrived.
Detectives and fire investigators are still unsure what originally caused the fire.
Police are investigating two aggravated break-and-enters on Saturday morning.
The break-ins occurred within an hour of each other at properties in Langdon and Baulkham Hills roads, Baulkham Hills.
Thieves forced entry at the Langdon Road home at 3.40am through a rear kitchen window.
A woman sleeping upstairs disturbed two men who were walking around downstairs with torches.
An hour later thieves broke into a Baulkham Hills Road house where an 80-year-old man was sleeping.
It's alleged the two men stole a flat-screen TV, a wallet with $300 cash, and a set of car keys.
A neighbour told police he saw the two men driving off in the victim's black Honda Accord.
The vehicle is still listed as stolen with the numberplate KKO 39Z.
Police charged a Baulkham Hills man with drug possession on January 13 after he left a licensed premises on George Street.
The 29-year-old was spoken to by the hotel's security staff before police later questioned him.
It is alleged he admitted to carrying a small amount of cocaine and handed police a small resealable bag with a white substance.
Police charged him with possessing a prohibited drug and he will face Parramatta Local Court on February 27.
The city fraud squad charged a Dural man with four counts of fraud on January 11.
The 46-year-old, who works with a Baulkham Hills-based accountancy firm, is alleged to have stolen up to $5 million.
On January 11 he attended City Central police station and was charged with a number of offences.
He will appear in the Downing Centre Court on January 25.
Trapped in car
A Kenthurst man was cut free from his car on January 13 after he lost control driving around a bend on Pitt Town Road.
The provisional driver, 19, slid his car off the road in wet conditions and hit a tree.
He was trapped in his car for 30 minutes.