Doctors examining the bruised body of murdered Hull student Libby Squire have revealed more details of her injuries at the trial against her alleged killer Pawel Relowicz.

Libby disappeared on January 31, 2019, and her body was discovered by fishermen in the Humber Estuary near Spurn Point seven weeks later, on March 20.

Relowicz, 26, of Raglan Street, is accused of raping and murdering her at Oak Road playing fields in the early hours of February 1. He denies the charges against him.

On Thursday, the trial heard from Home Office pathologist Dr Matthew Lyall, who conducted a post mortem examination on Libby's body at Hull Royal Infirmary on March 21, 2019.

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He told the court there was evidence that the body had been in the water for some time, which meant that any observations had to be made with a mind to the context that changes could have happened while she was in the water.

Libby had two lacerations inside her top lip which could not be ruled out as having happened when she was in the water, Dr Lyall said. He said that could have represented blunt trauma in that area.

He said there was no evidence of small hemorrhages around her mouth, which could be evidence of asphyxia - but added that their absence was "not conclusive".

Dr Lyall said: “It’s not conclusive but is something we look out for. It is like a little bruise but you tend to see lots of them at once around the lips or the eyes.

The prosecution say Libby's body was dumped in the River Hull at Oak Road Playing Fields

“They are a useful marker of it.”

Dr Lyall also described to the jury a number of suspected bruises found around Libby's body, including on her chest, abdomen and thighs.

He also told the court there was possible bruising on her upper right arm, which "could represent gripping, but I couldn't say it was a genuine bruise".

But he again said that he had to exercise caution over the possibility that some bruises could have occurred or changed after death.

Watch: Libby walking out into Beverley Road on January 31

Dr Lyall told the court there was also no injury found in bone samples taken from Libby's throat - but added that this did not rule out the possibility that she had been strangled, because the small bones are more flexible in young people and therefore less liable to break.

“For that reason, the absence of damage should not be as important a finding - they could be flexible and not fracture even if pressure was applied to the neck,” he said.

He told the court that it was also unclear whether Libby had been alive or not when she entered the water.

However, he also said Nicola Taylor, a forensic scientist, had found sperm cells detected on vaginal swabs taken during the post mortem examination that matched the DNA profile of Relowicz.

Police at the Grimsby Docks near to the RNLI lifeboat after the body of missing girl Libby Squire was recovered from the Humber Estuary

But he concluded that Libby's cause of death remained unascertained.

But he said he had looked into other mechanisms that might explain how she died, including drowning, hypothermia or violent assault.

He said: “A subtle asphyxial death remains a possibility, this could be some kind of smothering or neck pressure or a combination of both.”

But he added: “While drowning remains possible I am not prepared to say it is the likely explanation for her death.”

Under cross examination by defence barrister Oliver Saxby QC, Dr Lyall agreed that the pathological examination did not establish that she was killed - only a series of possibilities of how she might have died.

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He told Mr Saxby he could not prove that she had drowned, nor that she had been asphyxiated.

He told the court the level of decomposition to the body had made the post mortem examination harder, adding: “There could have been injuries - we just can’t see them.”

Relowicz denies charges of rape and murder.

The trial, which started on Tuesday, January 12, at Sheffield Crown Court before Judge Lambert, is expected to last four weeks.

The trial continues.