(Updates after meeting)
BEIRUT/JERUSALEM, Dec 16 (Reuters) - Senior Israeli, Lebanese and United Nations military officers met on Monday to defuse tension a day after a "rogue" Lebanese soldier shot dead an Israeli soldier on the border.
Sunday's incident jarred the relatively stable standoff between the two neighbours, which last saw major hostilities in the 2006 war between Israel and Lebanese Hezbollah guerrillas.
"We discussed concrete steps to strengthen the existing security arrangements (on the border) to prevent the recurrence of such incidents," the commander of the U.N. Interim Force in Lebanon (UNIFIL) said in a statement.
Major-General Paolo Serra said Israeli and Lebanese army officers had shown "full cooperation...in restoring calm in the area" after the cross-border shooting.
It was unclear exactly what happened, Serra said, although preliminary findings suggested it was the isolated action of an individual. The Lebanese soldier went missing after the incident but was later found, a Lebanese security source said.
Israeli Defence Minister Moshe Yaalon said earlier that Israel regards "the Lebanese government and the Lebanese army as responsible for what happens on their side".
"We will demand of the Lebanese army first of all an explanation as to what happened and whether this was indeed a rogue soldier; what they have done with him, and what the Lebanese army plans to do in order to prevent incidents of this kind," he said in a statement.
Israel said its soldier was driving near the border fence at its westernmost point of Rosh Hanikra when he was shot by a Lebanese army sniper.
Israeli troops who searched the frontier area later shot at two Lebanese soldiers who "made suspicious movements", hitting one of them, an army spokeswoman said.
The Lebanese security source said the Israelis fired into Lebanon during the night but had caused no casualties. A UNIFIL spokesman also said he was unaware of any Lebanese soldier being wounded.
Israel has lodged a complaint with UNIFIL, which has been stationed in southern Lebanon since 1978, and said it had heightened its state of preparedness along the border.
"We will not tolerate violations of our sovereignty along any border, and certainly not the Lebanese border," Yaalon said. (Reporting by Oliver Holmes and Dominic Evans in Beirut and Dan Williams in Jerusalem; Editing by Alistair Lyon)