JERUSALEM — Israel’s borders erupted in deadly clashes on Sunday as thousands of Palestinians — marching from Syria, Lebanon, Gaza and the West Bank — confronted Israeli troops to mark the anniversary of Israel’s creation. More than a dozen people were reported killed and scores injured.

With an unprecedented wave of coordinated protests, the popular uprisings that have swept the region touched Israel directly for the first time. Like those other protests, plans for this one spread over social media, including Facebook, but there were also signs of official support in Lebanon and Syria, where analysts said leaders were using the Palestinian cause to deflect attention from internal problems.

At the Lebanese border, Israeli troops shot at hundreds of Palestinians trying to force their way across. The Lebanese military said 10 protesters were killed and more than 100 were wounded. Israel said it was investigating the casualties.

In the Golan Heights, about 100 Palestinians living in Syria breached a border fence and crowded into the village of Majdal Shams, waving Palestinian flags. Troops fired on the crowd, killing four people. The border unrest could represent a new phase in the uprising against President Bashar al-Assad of Syria.