Normandy bunker today

Würzburg D (Finnish nick "Irja", a womans given name), a fire control radar was an essential part of Helsinki air defense. From Germany game 12 Messerchmidt 109 G 6 nitfighters on 12 February 1944. German night fighter direction vessel Togo cruised in the Gulf of Finland between Tallinn and Helsinki. 
-----
"In February 1944, the Soviet Union launched three massive bombing raids against Helsinki. The aim was to break the Finnish fighting spirit and force the Finns to the peace table. The raids were conducted on the nights of 6–7, 16-17 and 26-27 of February. Joseph Stalin had obtained British and American support for this measure at the Tehran conference in 1943. In this manner they hoped to force the Finns to break their ties with Germany and agree to a peace settlement with the Soviet Union.

Some 2,121 bomber approaches were counted in the three raids of February 1944, which dropped more than 16,000 bombs against Helsinki. Of the 34,200 shots fired against the bombers with heavy AA-artillery, 12,900 shots were with light AA-artillery. The Finns managed to lure the pathfinders by lighting fires on the islands outside the city, and only using the searchlights east of the city, thereby leading the pathfinders to believe that it was the city. Only 530 bombs fell within the city itself. The majority of the population of Helsinki had also left the city and the casualty figures were quite low compared to other cities of the period.

Of the 22-25 bombers destroyed by AA fire, four were shot down by German night fighters.
------
The Finnish Air Force responded to the air raids with series of night infiltration bombings of ADD airfields near to Saint Petersburg. Finnish bombers - Junkers Ju 88s, Bristol Blenheims, and Dornier Do 17s - either tailed or in some cases even joined formation with returning Soviet bombers over the Gulf of Finland and followed these to their bases. Once most Soviet bombers had landed the Finnish bombers approached to bomb both the landed and still landing Soviet bombers and then escaped in the ensuing confusion. The first major night infiltration bombing took place on 9 March 1944 and they lasted until May 1944. However Soviet casualties from these raids could not be estimated reliably.[3]" Wikipedia