1) Burst in suddenly 2) Burst suddenly 3) Come in 4) Enter 5) Enter uninvited 6) Erupt or intensify suddenly 7) Get in 8) Get into 9) Go in 10) Go into 11) Intrude 12) Intrude suddenly 13) Move into 14) Rush in 15) Rush in forcibly 16) To break or burst in suddenly 1) Intrude 2) Invade 
irrupt 1. To break or burst in suddenly. 2. To manifest violent activity or emotion; such as, a group of persons. 3. A reference to animals that increase suddenly in numbers through a lessening of the number of deaths.
flare 1 break open verb erupt or intensify suddenly; `Unrest erupted in the country`; `Tempers flared at the meeting`; `The crowd irrupted into a burst of patriotism`
to break or burst in suddenly. · to manifest violent activity or emotion, as a group of persons. · (of animals) to increase suddenly in numbers through a lessening of the number of deaths.
enter uninvited