The top of a cold drink bottle could spill crucial evidence in the murder trial of Stellenbosch student Hannah Cornelius.

DNA expert Warrant Officer Blanche Stubbs took to the stand at the high court in Cape Town on Monday‚ where three men - Vernon Witbooi‚ Geraldo Parsons‚ Eben van Niekerk - are facing robbery‚ hijacking‚ kidnapping‚ attempted murder and murder charges. A fourth suspect‚ Nashville Julius‚ is charged with robbery and kidnapping.

Cornelius and her friend Cheslin Marsh were hijacked in Stellenbosch in May last year. Cornelius had offered Marsh‚ a fellow student‚ a lift to his university residence in the early hours of the morning‚ when the accused men allegedly pounced upon them.

Video footage allegedly shows the man attacking the students. Cornelius’ body was found four hours later‚ while Marsh was left for dead in a field in Kraaifontein after a severe beating.

During her testimony‚ Stubbs said she found Witbooi’s DNA on the opening of a 2 litre bottle of Twizzer cold drink. Witbooi’s DNA was also found on the left side door of the hijacked car.

Parson’s DNA was found on a condom‚ which also contained Cornelius’ DNA. Stubbs said she found Cornelius’ DNA on a knife‚ and that it was mixed with that of unidentified people.

The trial continues.