Dad had affair with 17-year-old before killing family in homemade gas chamber

A killer dad had an affair with a 17-year-old girl before he gassed his wife and two children to death.

Fernando Manrique, 44, Maria Lutz, 43, and their kids Elisa, 11, and Martin, 10, were found dead, along with the family’s Bullmastiff Tequila, in their Sydney home in October 2016.

The father-of-two turned their house into a ‘gas chamber’ by setting up an elaborate system of pipes from the garden shed to the roof of the family home.

An odourless substance was then submitted throughout the property while the family slept.

Ms Lutz and the two children were found dead in their beds, while Manrique was found face down in the hallway.

An inquest into their deaths today laid bare details of the family’s dire finances, marital problems and revealed Manrique did intend to kill himself.

Deputy state coroner Elaine Truscott ruled Mr Manrique’s death a suicide and emphasised he had acted alone in killing his family,

The Sydney father, 44, chillingly planned their murder – ordering two cylinders of carbon monoxide and having them delivered to a friend’s home after his wife told him their marriage was over and he needed to find somewhere else to live.

The inquest was told the “dedicated” and “loving” Ms Lutz was completely unaware her husband, who had been made redundant, owed money to the Australian Taxation Office, had $28,000 in credit card debts and heavy mortgages.

The inquest found Manrique and Maria had been having problems in their marriage since 2013 due to Manrique’s constant travelling for work.

Fernando was also leading a double life with a 17-year-old bar girl in the Philippines, who he was supporting financially.

His wife had told friends the couple were no longer having sex and were sleeping in separate rooms.

Manrique confided in a friend about his extramarital affairs revealing he often ‘hooked up’ with other women when he was overseas and dated people for extended periods of time.

His Filipino girlfriend recalled Manrique appeared stressed during his final visit and was drinking heavily.

Post mortem reports revealed the all four had gas levels in their blood exceeding 70 per cent

Saturations exceeding 30 per cent are usual considered lethal.

Manrique and Maria were childhood sweethearts who emigrated from Colombia to Australia.

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