This is a sloppy story, so it’s hard to tell what’s really going on. The evidence of sloppiness is in the inconsistency in verb tenses in the lead graf, but more importantly in calling Marines “soldiers.” Here’s what I can gather:
The Marines requested permission for an urban warfare exercise. The mayor said he did not receive the request; he may or may not have told the truth. The marines showed up and were turned away.
What is absent from the story is whether the Marines received permission, or whether they did not hear back and forged ahead anyway. That is the critical fact, and it is missing.
If the latter, then the mayor was doing his job. You can’t just mount an exercise in a city neighborhood without warning residents and law enforcement that what appears to be urban combat is just an exercise. That is how folks get shot for no good reason.
Either way, someone dropped the ball. Either the city granted permission and someone didn’t make the appropriate preparations or tell the mayor, or the Marines failed to receive permission and went ahead anyway.