BALTIMORE ( — A baseball game between the White Sox and the Orioles in Baltimore postponed because of safety concerns related to the unrest developing in the city on Monday.

Maryland governor Larry Hogan put National Guard ‘on alert’ Monday to respond to looting and violence in the city.

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President Barack Obama is pledging the federal government’s help to respond to riots that broke out in Baltimore following the funeral of Freddie Gray.

Gray had died while in police custody, raising questions about his treatment.

The Orioles announced the decision to postpone the game about 30 minutes before the opening pitch would have taken place.

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Rioters have looted stores and thrown rocks and bricks at Baltimore police in the wake of Gray’s mysterious spinal injury. The epicenter of the protests is less than a mile from the ballpark.

Some 1,000 fans were inside the stadium when the game was called off, and many gates already had been closed.

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