A post mortem later revealed that Mr Kulinski had been stabbed seven times.
The prosecution allege that Piotr Zygner and Sylwester Kawalec were the two who carried out the attack.
They, and all the other defendants, deny the charges.
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Emma Jesson brings you Saturday night's forecast
Christmas Eve which could be rather frosty, and at present, Christmas Day itself looks like being cold and clear with a few wintry showers
There is a bit of everything on the way this weekend. Here is your forecast: