Walmart investigates shootings at Ohio store and outside Alaska store

Shooter in Ohio wounded four people before killing himself, days after two people were shot and killed outside a Walmart in Alaska

Walmart says it is working closely with investigators to try to determine why a shooter opened fire at one of its stores in Ohio and wounded four people before killing himself late on Monday.

The attack came during a year that - as of early Tuesday - had so far seen the US report about 610 mass shootings, according to the Gun Violence Archive.

The Associated Press contributed reporting