Turkey has again summoned the Russian ambassador after a second violation of its airspace by a Russian warplane operating in Syria in two days.It did the same after the first violation on Saturday, after which two Turkish F-16 jets were scrambled, reports BBC.Turkey said the second violation occurred on Sunday.Nato has urged Russia to end air strikes "on the Syrian opposition and civilians". Russia says it is targeting Islamic State and other Islamists.Russia said Saturday`s violation was for just a few seconds and due to poor weather. It has not officially reacted to Sunday`s incident.Saturday`s interception took place near Yayladagi in the southern Hatay region, Turkey says.A statement by Nato`s 28 members, which include Turkey, warned of "the extreme danger of such irresponsible behaviour" and urged Russia "to cease and desist".US Secretary of State John Kerry said Turkey would have been within its rights to shoot the jets down.