What would have been the consequences had the grenade gone off?
A Georgian man has been sentenced to life in prison for throwing a grenade at a rally attended by US President George W Bush in Tbilisi last May.
Vladimir Arutyunian was found guilty on charges including terrorism, treason, attempted assassination and the killing of a police officer, the judge said.
The grenade landed 30m (100ft) from Mr Bush and the Georgian leader, who were standing behind bullet-proof glass.