Yaalon toured Israel's northern frontiers with Syria and Lebanon alongside army chief of staff Benny Gantz, as the military beefed up its presence in the area.
"We need to be operational and ready to face any challenge," Yaalon said in a statement.
"Israel will hold responsible governments, regimes and organisations on the other side of our northern borders over any violation of Israel's sovereignty, or an attack on soldiers or civilians," he said.
Israel neither confirmed nor denied responsibility, but it has carried out several such strikes over the past two years, stressing its policy of preventing arms transfers to militant groups.
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Hezbollah has responded in the past with explosive devices placed along the frontier.
Hezbollah leader Hassan Nasrallah is to give a speech next Friday reacting to the Israeli raid, in which a general of Iran's elite Revolutionary Guards was also killed.
"The IDF (military) is prepared for any scenario, and will, on the one hand, exercise proper discretion, and on the other, operate with determination and the required intensity," he said.
Israel has deployed its Iron Dome missile defence system in the north, where local media say it is amassing tanks and infantry reinforcements.