Yes. Particularly if their sources of natural food are in short supply. Boar feed on a wide variety of food and will readily feed on agricultural crops. Favourite crops include sugar beet, maize, potatoes, oats, wheat and grassland. In England, most of the damage reported has been damage to maize crops and rooting in grassland.
Wild boar will also eat carrion such as dead livestock, and they have been reported to take dead and very weak lambs.