The ballot of thousands of RMT and TSSA union members on London Underground against major job cuts is continuing.
The unions are in dispute over management plans to axe 800 station staff as part of cost-cutting measures. The ballot ends on 11 August.
Tube bosses last week admitted to the RMT that cuts mean that services are running on dangerous infrastructure dating back to the 1920s.
Bob Crow, RMT general secretary, said, “The RMT will not sit back and wait for a tragedy before we act.
“Staffing and financial cuts are turning the underground into a death trap and the senior management right up to Boris Johnson know that.”