A comet flew over the empire for forty days, heralding bad news to come. Raiders struck from the west, coming within mere miles of Constantinople. But the biggest threat lay in the south, where a border dispute threatened to reignite the war between the Romans and the Persians. Since Belisarius was still in Italy, Justinian had to send other generals to attempt to resolve the matter peacefully. Both failed spectacularly. The Persian king Khosrau seized on this as a pretext for invasion. But instead of laying expensive sieges to the cities, he simply extorted them for tribute in exchange for being left alone by his army. As he advanced north, he took advantage of every opportunity to mock Justinian and remind him how little power he had to push the Persians back. Finally, the city of Antioch refused to surrender to Khosrau and he made quick work of it, convincing Justinian at last of the need to pay his own tribute to the Persians to make them go away. This bought him enough time for Belisarius to return, but even his great general was unable to make much progress. At last, he found himself pinned down in an un-winnable fight... which the Persians mysteriously decided not to engage against him. They did not want to risk contact with the Romans, whom they feared were rife with disease.