From the video’s YouTube page:

On Israeli Independence Day, same day that marks the premeditated ethnic cleansing of ~700,000 Palestinians in order to create a Jewish majority by force, the Israeli police besieged the offices of Zochrot at the heart of Tel-Aviv in order to prevent the activists present from holding a very symbolic memorial activity for that day.

This video shows arriving at the place already besieged by the police, the people inside prevented from leaving and those outside prevented from entering the office building.

At the time of writing this, police is still present as well as over 100 citizens demonstrating outside the offices. The police attacked and arrested some demonstrators, while preventing entry-exit to the office.