'It has been a shock': Latino community pays tribute to Maria Claudia Lutz and family at mass in Sydney

The voices of the St Mary's Cathedral choir soared but the mood was sombre on Sunday as a prayer was offered "for those who have died in tragic circumstances".

To the left of the altar sat a small white board adorned with pink flowers and bearing photographs of Maria Claudia Lutz and her smiling children Martin and Elisa.

Martin and Elisa were found dead in the house with their parents.  Photo: Supplied

The tribute to the 43-year old mother, who was found dead in her Davidson home along with her young children and husband, Fernando Manrique, was placed there by Sydney social worker Isabella Almendrades.

Ms Almendrades met Mrs Lutz and her husband when they moved to Sydney from Colombia a decade ago.

"I felt that I had a moral obligation to support them, to show them we are thinking of them," said Ms Almendrades, who organised for members of the Latino community in Sydney to attend the 10.30am mass.

"It has been a shock for the community," she said.

The bodies of Mrs Lutz, Martin, 10, Elisa, 11, and Fernando, 44, were found in their closed-up Davidson home last Monday.

Detectives believe gas deliberately filtered through the sprawling home in Sydney's north is the most likely cause of death. Both children had autism.

It is understood Mr Manrique had set up an account with a gas company to order carbon monoxide in recent weeks.

After the gas was delivered, understood to be to an address that wasn't his home, the tanks were kept outside his property, unbeknown to the rest of the family.

A prayer was offered during the solemn mass to remember those who had died in tragic circumstances, and particularly the Lutz-Manrique family.

The Colombian family of Mrs Lutz is preparing to arrive in Australia to take their loved ones back home.

Ms Almendrades said she wanted to show the family they were "united in their pain".

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