TRADE unionists commemorated the anniversary of one of Britain's worst mining disasters on Saturday.

An underground explosion at Pretoria pit, Atherton, in the historic county of Lancashire killed 344 men and boys on December 21 1910.

It was thought to have been caused by an accumulation of gas from a roof collapse the previous day and a faulty pit lamp.

There was only one survivor of 345 men and boys who descended that day.

Many families lost several members. The worst affected was the Tyldesley family, in which Miriam Tyldesley lost her husband, four sons and two brothers. 

The pit’s owners, the Hulton Colliery Company, resumed production one week later, leaving most of the victims entombed.

The sole survivor, John Baxter, died in 1973.

Saturday’s commemoration was organised by Salford Trade Union Council and the Irwell Valley Mining Project.