A German student has told a jury he was stabbed eight times in an attack that led to his friend's death in Dublin.

Robert Rinker has been giving evidence in the trial of a young man and a teenager accused of murdering Thomas Heinrich in December 2012.

With the help of a German interpreter, Mr. Rinker has been outlining what he remembers happening outside an apartment at St. Anthony's Road in Rialto in the early hours of December 1st 2012.

Following a night out, he said Thomas got involved in a row with two youths from his balcony. They left but Mr. Rinker said they returned with knives a short time later.

He armed himself with two kitchen knives and dashed downstairs to scare them off.

Thomas joined him and he said the two friends found themselves backed up against a wall. Mr. Rinker described dropping his weapons and tackling one of his attackers in a fight that resulted in him being stabbed eight times.

Thomas Heinrich was stabbed in the stomach and he died from his injuries in hospital.

Wesley Kelly of St. Anthony's Road in Rialto and his co-accused, who cannot be named because of his age, deny murdering Mr. Heinrich and they have also pleaded not guilty to attacking Robert Rinker.