Another child and a 26-year-old woman were also injured yesterday as the group worked in a field during a violent storm in the town of Mesa Cuata, in the central Guanajuato state.
The dead children were aged three, five, nine and 14, a Guanajuato civil protection official told AFP by telephone.
The other victims were three women aged 19, 32 and 44.
The town where the tragedy took place is in the mountainous Sierra Gorda region.