A total of 20 hostages were killed by the terrorists in an attack at Holey Artisan Bakery of Gulshan-2 in the capital.Inter Service Public Relations Directorate confirmed the information at a press conference held at Army headquarters on Saturday.Gunmen stormed the Holey Artisan Bakery cafe late on Friday before troops entered almost 12 hours later.Six of the attackers were killed and one was arrested in this connection.