Protesting against the death of an old man, angry locals of the Ghatikia area on the outskirts of the city on Thursday set fire an apartment under construction.According to reports, the old man died after coming in contact with a live wire in the premises of the Galaxy Trident apartment in the morning.The Khandagiri police rushed to the spot and pacified the irate locals, who demanded immediate arrest of the builder.The body of the unidentified old man was later taken for postmortem to the Capital Hospital.