In the meantime Labienus, one of Caesar's most trusted generals, was wintering in the territory of the Treveri, and also came under threat when news of the Eburones rebellion spread. Eventually, he killed the king of the Treveri, Indutiomarus. "This affair having been known, all the forces of the Eburones and the Nervii which had assembled, depart; and for a short time after this action, Caesar was less harassed in the government of Gaul." In the following year Caesar entered the country of the Eburones, and Ambiorix fled before him. Cativolcus poisoned himself with a concoction from a yew tree. The country of the Eburones was difficult for the Romans, being woody and swampy in parts. Caesar invited the neighboring people to come and plunder the Eburones, "in order that the life of the Gauls might be hazarded in the woods rather than the legionary soldiers; at the same time, in order that a large force being drawn around them, the race and name of that state may be annihilated for such a crime". The Sicambri, from east of the Rhine, were one of the main raiders. While Caesar was ravaging the country of the Eburones, he left Quintus Tullius Cicero with a legion to protect the baggage and stores, at a place called Aduatuca, which he tells us, though he had not mentioned the name of the place before, was the place where Sabinus and Cotta had been killed. The plan to take advantage of the Sicambri backfired when the Eburones explained to the Sicambri that the Roman supplies and booty, not the refugees, were the most attractive target for plundering.