* Hariri's son makes rare visit to Beirut * Late statesman was killed 10 years ago in bombing * International tribunal has indicted Hezbollah supporters (Recasts with Hariri speech) By Sylvia Westall BEIRUT, Feb 14 (Reuters) - Former prime minister Saad al-Hariri, speaking on a rare visit marking the 10th anniversary of his father's assassination, said dialogue with Hezbollah was necessary to ease sectarian tensions in Leba**n. Five members of Lebanese Shi'ite group Hezbollah have been indicted by an international tribunal over the 2005 killing of Rafik al-Hariri, who was commemorated on Saturday in the Lebanese capital. The group has denied any involvement in the murder, which pushed Leba**n to the brink of civil war and still stirs emotions 10 years later.