Pockets of trapped air were in the lungs of murdered school girl Billie-Jo Jenkins, the Old Bailey heard.

Sections of the 13-year-old's lung tissue were displayed on slides in court showing bubbles lodged in her airways.

At the murder retrial of Billie-Jo's foster father Sion Jenkins evidence was heard from two lung experts yesterday.

New York-based Dr William Travis said forced air from some source probably represented an upper airway blockage in Billie-Jo's lungs.

Yesterday Professor Andrew Nicholson, consultant histopathologist at the Royal Brompton Hospital in London, said there was blood evidence in about half of Billie-Jo's small lower airways. Blood had also got into the inner lining of her heart.

Later he said that, had the entirety of Billie-Jo's lungs been examined, he would have expected to have seen "millions" of bubbles.

Jenkins, 47, is alleged to have struck Billie-Jo at least five times with a metal tent peg in a fit of rage as she painted patio doors at the family home in Lower Park Road, Hastings.

The former deputy headteacher at William Parker School in Parkstone Road, Hastings, was jailed for life at Lewes Crown Court in 1998 after the Crown claimed microscopic blood spots found on his clothes proved he had bludgeoned her.

His conviction was quashed at the second attempt last July at the High Court when his defence team cast doubt on the blood spots evidence, prompting a retrial.

Jenkins's defence team claims the mist of blood formed on his clothes as he tended her. Jenkins denies murder. The case continues.