ZKP.

About a hit on the building of Staff of Black Sea Fleet. Immediately for people who may have questions: NOBODY IS in this building except for maintenance and guard crew. During war time all C4 departments of the Staff operate out of ZKP (Запасной Командный Пункт--ЗКП)--a Reserve Command Post, which is underground and is very difficult to identify and attack. So, the attack is primarily for PR reasons, militarily it has a very low value, plus disruption of the civilian traffic in the area of Lenin's Street, Nakhimov's Square, Nakhimov's Ave and on the hill where the Staff and Rear Service of the Fleet are located. 

Per US P-8 Poseidon in the vicinity in the international air space--this is US MO--fight through proxy, hide behind them. Poseidon was scanning electromagnetic picture of Sevastopol's Air Defense during attack for "library" reasons and transfer of data to VSU for the next attack. In real war, there would have been no US assets anywhere above the Black Sea because they would have been all shot down. Pentagon knows this, but, as was pointed out many times--they see for the first time the real war, so they want "to take part". Expect some response from Russia, Misters Kalibr, Iskander and Geran will be very busy in the next few days.