Israel carried out airstrikes on the Gaza Strip late on Thursday evening "in response" to "arson balloons" launched by Hamas, the Israeli military said.

It is the second time in as many days strikes have occurred with the region's cease-fire looking increasingly vulnerable.

There were no immediate reports of casualties from the strikes, which could be heard from Gaza City.

Shaky cease-fire

Almost 250 people died, dozens of which were children, during an 11-day conflict last month, which was brought to an end by an Egypt-brokered cease-fire.

But that peace arrangement is now hanging by a thread after activists mobilized by the territory's militant Hamas launched incendiary balloons into Israel for a third straight day, prompting the Israeli reaction.

Hamas military compounds targeted

"Over the past day, arson balloons were launched from the Gaza Strip into Israeli territory," Israel Defense Forces (IDF) said in a statement.

"In response... fighter jets struck military compounds and a rocket launch site belonging to the Hamas terror organization," the military statement added. "The IDF has increased its readiness for various scenarios & will continue to strike Hamas terror targets in Gaza."

US: 'Unwavering commitment to Israel's security'

US Secretary of State Antony Blinken said he had spoken with Israeli Foreign Minister Yair Lapid, recently installed as part of new Prime Minister Naftali Bennett's cabinet.

"We discussed America's unwavering commitment to Israel's security, our bilateral relationship, and the challenges ahead," Blinken tweeted after the Israeli airstrikes.

They also discussed "the need to improve Israeli-Palestinian relations in practical ways," State Department spokesman Ned Price said in a separate statement, with no mention of the airstrikes that have taken place over the last two days.

The new exchanges of fire come as Egypt tries to consolidate the cease-fire it helped arrange.

jsi/sms (AP, AFP)