This is the van from which two men photographed everyone entering a Brussels hotel where Catalan president Puigdemont held a meeting this Monday with political colleagues to discuss the progress of negotiations over the investiture. The photo was taken from inside the hotel.
Among the meeting's attendees were ministers Clara Ponsatí and Lluís Puig, the spokesperson for the Junts per Catalunya parliamentary group, Elsa Artadi, and her deputy, Eduard Pujol.
The presence of the vehicle and the activity of its occupants was denounced by Míriam Nogueras (link above), a PDeCAT deputy in the Spanish Congress. In a tweet, Nogueras asked Spain's deputy PM whether the country's intelligence service, which falls within her ministry, was "spying on elected deputies in another country".