That was a very touching, thoughful expression in homage and tribute to Ariel Sharon. It is a tradition among Jews that when being informed of someone's passing, to say
Boruch Dayan Emes .. blessed be the one true divine Judge. It is not a blessing in the traditional sense where its recital includes the words
Barukh atah Adonai Eloheinu melekh ha’olam.
When responding to the news of death, it is customary to merely say, Boruch Dayan Emes.