LONDON: A British couple accused of killing their six children in a house fire started the blaze themselves as part of a ''plan that went horribly wrong'', a court has heard.

Prosecutors claim that Mick Philpott, 56, and his 31-year-old wife Mairead set fire to their house in Derby, in the Midlands, last May in a bid to frame his ex-girlfriend and claim custody of the four children they had together.

The Philpotts, along with a third defendant, Paul Mosley, 46, each denied six counts of manslaughter at Nottingham Crown Court on Tuesday.

As their trial opened, Mr Philpott tried to leave the dock as the jury listened to the telephone call the couple made to emergency services when the fire took hold in the early hours of May 11. Mrs Philpott was heard screaming on the tape, while her husband told the operator: ''I can't get in.''

The jury heard that neighbours tried to rescue the children, aged five to 13, but were overwhelmed by smoke and flames. When police carried the children's bodies from the house, their father had to be restrained.