India, Jan. 12 -- TEHRAN, Iran, January 12 - Iran summoned the British ambassador to Tehran on Sunday, formally protesting after a demonstrator tore down the Iranian flag at its embassy in London. The diplomatic rebuke comes amid heightened tensions over Iran's deadly domestic crackdown and Western condemnation of its government's actions.

Iran's Foreign Ministry summoned the envoy to convey a "strong protest" over an incident at its London embassy on Saturday. Video footage showed a protester removing the official Iranian flag and briefly replacing it with the pre-revolutionary flag, while other clips depicted embassy staff removing the substitute banner as crowds chanted insults. Iran's state broadcaster IRIB reported the summons.

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