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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The Westminster terror attack dominates the front pages of Thursday's newspapers.
A timeline of exactly what happened.
Tobias Ellwood, MP for Bournemouth East and Foreign Office Minister, attempted to save the life of the stabbed officer in Westminster.