Looking for zombie movie

The zombie movie was out before 1984 for sure. I remember two scenes.

The first, the outbreak has happened and the zombies are running through a town...there is a man with a rifle or shotgun and a young zombie kid in front of him. He shoots the kid and the kid stumbles back a couple steps into a fence (maybe there was no fence) and then the kid would walk forward again. The man shot a few times with the same result.
The next scene, there is a girl slowly walking down a long hall that was not very well lit. She sees a person laying on the floor with another person kneeling beside, hunched over the body. She creeps forward calling out a friends name to see if it was them and when she gets closer, the hunched figure looks up and has (what looks like Sloppy Joe) hamburger stuff coming out of its mouth from eating the guts. Please help me find this title. Thanks much!