MSNBC “Hardball” host Chris Matthews announced on air Monday that he was leaving the network, days after being accused of making inappropriate flirtatious comments to a guest and comparing Sen. Bernie Sanders’s victory in the Nevada caucuses to the World War II Nazi takeover of France.

A person familiar with Mr. Matthews’s decision said that his retirement was already “imminent,” but that the events of the past few weeks accelerated his exit from the network.

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