The Punjab Boundary Force was set up on 1 August 1947 under Major General Thomas Rees to keep order across twelve districts of central Punjab during the transfer. It had about 25,000 men.
Twelve districts held about fourteen and a half million people. The force was mixed, with Indian, Pakistani and British officers, and its units were themselves communally composed at a moment when communal composition determined everything.
It could not hold. Columns of refugees of hundreds of thousands were moving in both directions along the same roads. Trains were stopped and their passengers killed. Villages were burned.
The force was disbanded on 1 September 1947, after a month, and responsibility handed to the two new governments.
Estimates of the dead in Punjab in 1947 run between two hundred thousand and a million. Between ten and twelve million people moved. Neither figure is a count and neither state has ever conducted one.
It is the largest forced migration in recorded history and there is no official register of the dead on either side.
It was set up in July 1947 to police the twelve districts through which the line was expected to run, with about twenty-three thousand men and a mixed command.
It was far too small for a population of fourteen million and it was itself dividing, since its own soldiers were being posted to two future armies.
It was disbanded at the end of August, five weeks after it was formed. The killing was at its worst in the weeks after it was withdrawn.