(Bloomberg) -- Violence flared along the volatile Israel-Gaza Strip border early Saturday, with Palestinian militants firing volleys of mortars and rockets and the Israeli air force striking sites inside the Hamas-ruled enclave, including a tunnel dug to infiltrate the country’s south.

No serious casualties were reported on either side. The military said 31 projectiles were fired overnight, most of them mortar shells, and that six were intercepted by its missile-defense systems. Israeli aircraft struck a tunnel dug from Gaza for militants to enter Israel to carry out assaults, as well as military compounds including a site used to prepare kites and balloons to carry out arson attacks, it said.

Hamas spokesman Fawzi Barhoum said the attacks from Gaza were meant “to force the enemy to stop the escalation.”

Tensions along the border have been high since near-weekly protests against Israel began in late March. Nearly 140 Palestinians, some of them unarmed, have been killed in the confrontations with the Israeli military, and militants have destroyed thousands of acres of farmland and nature reserves in southern Israel, and tried repeatedly to break through the frontier.

At the latest protest on Friday, two people were shot dead -- a 15-year-old who tried to breach the border and an 18-year-old who died of his wounds on Saturday. The military said soldiers were attacked during the protests with grenades, explosive devices and rocks.

While protest organizers have said the demonstrations that began in late March are meant to be peaceful, Israel says Gaza militants use them as cover to attack it.

To contact the reporters on this story: Amy Teibel in Jerusalem at ateibel@bloomberg.net;Saud Abu Ramadan in Jerusalem at sramadan@bloomberg.net

To contact the editors responsible for this story: Alaa Shahine at asalha@bloomberg.net, John McCluskey

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