ROME: Four Indian-origin Sikh men drowned in a sewage tank on a cattle farm in northern Italy due to the carbon dioxide fumes coming out from the cow manure, according to media reports.
The incident happened on Thursday at a cattle farm in Arena Po near Pavia, a city in south Milan, ANSA news agency reported on Thursday.
Out of the deceased, two were brothers- Prem, 48, and Tarsem Singh, 45- who were running the farm.
The duo registered their farm in 2017.
The other two were workers, identified as Arminder Singh, 29, and Manjinder Singh, 28.
Initial investigations reveal that the three men jumped to rescue a worker who was emptying the tank to use the manure as a fertiliser on the farm's fields, the BBC reported.
Investigators suspect that the four died due to the carbon dioxide fumes coming from the cow manure, the report said.
The victims' wives raised the alarm when the men failed to turn up for lunch.
They rushed to the scene and spotted one body in the sewage.
The women then called in the firefighters, who donned masks and emptied the tank to recover all the bodies, the report said.
Italian media reported that the farm, which produces milk and veal cattle, is one of the biggest in the Pavia region.
The Italian Agriculture Minister Teresa Bellanova in a tweet condoled the deaths, saying "safety at work is an inalienable right and we must make every effort to ensure it is respected".
She was a farm labourer herself as a teenager.
Italy's public broadcaster Rai said the Arena Po tragedy brings to 486 the total of deaths in work accidents in Italy this year - the highest toll since 2016, the BBC report said.