Hadhrat Ali bin Abi Taalib Radiallahu Anhu says, "I know of no person who did not make Hijrah secretly except for Umar bin Khattaab Radiallahu Anhu. When he decided to make Hijrah, he hung his sword from his neck, carried his bow on his shoulder and took a few arrows in his hand. He then proceeded to the Kabah where the leaders of the Quraysh were sitting in their gatherings. He went around the Kabah seven times and then performed two Rakaahs salaah by the Maqaam Ibraheem. Thereafter, he approached each gathering separately, saying, "May your faces be disfigured! Whoever wants his mother to mourn him, his children to become orphans and his wife to become a widow should meet me behind this valley (to try and stop my Hijrah)." None dared follow him out.
Ibn Asaakir, as quoted in Muntakhab Kanzul/Ummaal (Vol.4 Pg.387)