The wives of two brothers facing trials over murder and drug smuggling charges are selling their million-dollar homes to pay the government $3million of unpaid tax.

Sydney brothers Mahmoud 'Brownie' Ahmad and Ahmad 'Rock' Ahmad are both in custody after their arrests last year.

Mahmoud, 35, is accused of shooting and killing a man in a brazen gunfight outside a smash repair business in southwest Sydney in 2016.

Sydney brothers Mahmoud 'Brownie' Ahmad and Ahmad 'Rock' Ahmad (pictured left and right with his wife Latifah Ahmad) are both in custody awaiting trial

Latifah Ahmad, 39, put her lavish home (pictured) in Lavender Ave, Punchbowl on the market in July 2016 for $1.9million - but is yet to sell up

His older brother, the family patriarch, was arrested and charged last August over an alleged multi-million-dollar international drug-smuggling ring.

Now the pair are being chased by the taxman, forcing their wives to find the money.

Mahmoud's wife, Carmen Piscioneri, 32, sold the couple's five-bedroom home in Highview Ave, Greenacre for $1.2million on April 4.

Mahmoud 'Brownie' Ahmad (pictured) owes the taxman $1.5million

Her sister-in-law Latifah Ahmad, 39, put her lavish mansion in Lavender Ave, Punchbowl on the market in July 2016 for $1.9million - but is yet to sell up.

She is living in a rented Bankstown townhouse while her husband remains in custody, reported The Daily Telegraph.

Mrs Ahmad reportedly owes the taxman $1.5million while Ms Piscioneri has to pay $1million.

The wife of convicted killer Walid Ahmad, a third Ahmad brother who was assassinated at a Sydney shopping centre in 2016, allegedly has to pay a more modest $230,000.

When contacted by Daily Mail Australia, an Australian Taxation Office spokesman declined to comment for confidentiality reasons.

Mahmoud was arrested by NSW Police at Sydney airport in March 2017 immediately after touching down from Lebanon, where he was living for a year.

He told Fairfax Media while in Lebanon that he had 'nothing to clear up' with authorities.

'Tell the cops to get their facts right first. I'm not running or hiding so f*** off,' he said.

Mahmoud (centre being arrested) was aprehended by NSW Police at Sydney airport in March 2017 immediately after touching down from Lebanon, where he was living for a year