Read the following context and choose the best option to answer the question.
Context: DENVER We d . August 27th - There were some tense moments at the Unconventional Denver convergence space Wednesday morning when police set up a perimeter around it and attempted to enter and search the building . Security at the space demanded a search warrant when police asked to enter the space . Legal aid was called to the scene immediately where video and written accounts were taken . Police were unable to obtain a warrant and left after some time , but not before arresting 2 activists outside the center .
Question: What may have happened before the police left ?
Options: 
- They arrested three protesters .
 - None of the above choices .
 - The tried to get into the building .
 - They searched the building .


The tried to get into the building .