Sylvia Plath wrote to her therapist claiming that Ted Hughes had beaten her two days before she miscarried their child, it is reported, in a series of previously unseen letters at the centre of a legal battle.

The 14 letters are said to allege "physical abuse and psychological torture at the hands of her husband" and shed new light on the turbulent relationship between the two writers. They will also fuel the fire of Plath supporters who have long labelled Hughes as emotionally abusive and believe his behaviour - including his infidelity - drove her to take her life.

Plath died in February 1963, aged 30. She killed herself as her young children lay sleeping in the next room, leaving out milk and bread for them in a final act of maternal love.