The Alliance party's deputy leader Naomi Long has told Daybreak that "democracy must prevail" after a police car was petrol-bombed outside her office in Belfast last night.
She said: "My heart is broken for Northern Ireland this morning.
"I thought we were moving away from this but while my heart may be broken, my resolve is not. Democracy must prevail."
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A man, reportedly armed with a knife and a baseball bat, has been detained close to the event.
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