Donald Trump threatened to deploy National Guard troops Sunday to yet another Democratic stronghold, the Maryland city of Baltimore, as the US president seeks to expand his crackdown on crime and immigration.

The Republican's latest online rant about an "out of control, crime-ridden" city comes as Democratic state leaders -- including Maryland Governor Wes Moore -- line up to berate Trump on a high-profile political stage.

Trump this month deployed the National Guard to the streets of Washington, in a widely criticized show of force the president said amounts to a federal takeover of US capital policing.

In June he controversially ordered nearly 5,000 troops to Los Angeles -- ostensibly to quell protests against immigration enforcement raids -- triggering ferocious opposition from Calif

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