Details differ, depending on the source. But generally, all agree, that on December, 2nd, a recon batallion of the 258. infantry division (sorry for the mistake -it was not a tank division) entered Khimki. It's several kms from the Kremlin, but if you consider, that in 40ies most Moscow was covered by low buildings, they could really see the domes(copulas) of the Kremlin towers.
Germans waited for the support till next morning, until they were pushed back by a quick-combined unit of local armed militia supported by several tanks from a reserve company, which was incidentally in the area. There was no large regular units on Russian side in that part of Moscow!
The first person, who passed information about this incident to so-called "Western world", was W.Shearer, an american correspondent of "Chicago Tribune" in Berlin, who wrote a note to his paper.