Mahayana Buddhism does not tolerate the consumption of any kind of meat. Not only those that do not qualify as being clean but also meat from the animals that died of illness. Where can we find proof of this view in the Mahayana canon? Mainly the Lankavatara Sutra and the Nirvana Sutra. There are others, but these two provide the most explicit explanation.
[Excerpt from Luminous Wisdom Book Series 1: The Right View ~Why Vegetarian?]