Mumbai, India (CNN) — Countless bullet marks, a hole punched in a wall by a grenade and windows covered with plastic bear testimony to a carnage that left six people dead in Mumbai’s Chabad House last year when terrorists besieged several sites around the financial hub of India. Among those slain in the coordinated strikes, which left 160 people dead and lasted four days, were young Rabbi Gavriel Noach Holtzberg and his pregnant wife who ran the Mumbai headquarters of the Chabad community — an Hasidic Jewish movement. “This house was lively, full of happiness, full of friends,” said Rabbi Avraham Berkowitz, who came from Russia to oversee Chabad in India after the attacks. “That is what we have to bring back.” Once throbbing with Jewish visitors who were welcome to come to pray, eat kosher meals and celebrate religious holidays, the Jewish center, tucked away behind a causeway, is like a shrine. In keeping with Jewish tradition, the site has been in year-long mourning since the November 2008 attacks. Mumbai’s Jewish community is close knit. They get together every Friday, now in a secret location out of safety concerns. Though attendance is down, there are newcomers who join to show their support, Berkowitz said. They are struggling to find answers, said Yehuda Krinsky, head of the Lubavitch World Headquarters, who is in Mumbai to mark the first anniversary of the 2008 strike with a remembrance ceremony at the Jewish center. “The question why, like a lightning bolt …