Here-rǽs

According to the Old English Dictionary:

es;

here-rǽs

m. An inroad by an army, a raid by the Danes :-- Gif hwæt fǽrlices on þeóde becymð, beón hit hererǽsas, beón hit fǽrcwealmas, beón hit miswyderu, Wlfst. 271, 2. here-ræs