Who killed Archimedes?

It is said that when Roman soldiers entered the city, Commander-in-Chief Maceiras, out of admiration for Archimedes' talent, ordered that the saint should not be harmed. Archimedes didn't seem to know that the city had been breached, and he was addicted to mathematics. A Roman soldier suddenly appeared in front of him and ordered him to go to Maceiras. Archimedes sternly refused, so Archimedes unfortunately died by the soldiers' sword.