Two unknown assailants wounded the security guard at a heavy machinery storage site in Kibbutz Einat on Saturday.
According to Israel Radio, the guard was attempting to prevent the assailants from setting fire to the machinery. Two machines were set on fire and other equipment was damaged in the attack.
The guard's son fled the scene of the attack and alerted police.
The site's owner told police he believed the attack was motivated by a business disagreement.