Michigan Gov. Rick Snyder has vetoed legislation that would allow concealed weapons in churches, schools and daycare centres in that state.

The Republican governor told The Associated Press on Monday he was scrutinizing the bill after Friday's massacre at a Connecticut school. He also drew on his own memories of a fatal shooting in his college dormitory more than three decades ago.

Snyder said in a release Tuesday that public venues need clear legal authority to ban firearms "if they see fit to do so."

The legislation would have prohibited openly carrying guns in churches, schools and daycare centres while allowing permit holders to carry concealed weapons. But they couldn't if the locations declare themselves weapons-free zones.

Under Michigan law, people may openly carry guns in those and other locations but not concealed weapons.