It took them long enough, too long in my opinion but the Boston Red Sox have canceled tonight's game against the Kansas City Royals. No makeup date has been announced as of yet.
The Royals do not come back to Boston again this season so it's possible this game could be made up this weekend. I'm guessing that'll depend on what happens with the current situation. If not, it'll be on a mutual off day for both teams.
Here's the release from the Red Sox:
BOSTON, MA - Tonight's Boston Red Sox game at Fenway Park has been postponed to support the efforts of law enforcement officers. The Red Sox were scheduled to open a 3-game series against the Kansas City Royals at 7:10 p.m.