Smoke rises following an Israeli attack on the Gaza Strip as it seen from the Israeli side of the border, May 29, 2018. Photo: Yonatan Sindel / Flash90.

An Israeli air strike in the Gaza Strip killed a member of the Islamist group Hamas on Thursday and wounded three others, Hamas sources and medical officials said.

The Israeli military confirmed it had carried out a strike targeting Hamas terrorists who were about to launch balloons rigged with flammable material over the border into Israel.

Hamas sources said the casualties were security men working at an observation post near Rafah, in the southern Gaza Strip.

After the air strike, the Israeli military said Palestinian terrorists had fired mortar bombs at Israeli soldiers across the border, but no casualties had been reported.

Fires caused by incendiary helium balloons and kites launched by Palestinians in Gaza have ravaged tracts of farmland in Israel in recent months. Israel has vowed to stop the attacks, even at the risk of wider conflict.

Clashes at the Israel-Gaza border have kept tensions high for months. More than 130 Palestinian rioters have been killed by Israeli forces since March during weekly disturbances at the frontier.

Israel says Hamas has been orchestrating the unrest to provide cover for terrorists’ cross-border attacks.

Cross-border violence surged on Saturday when Palestinian terrorists fired more than 100 rockets into Israel and the Israeli military carried out dozens of air strikes in the Hamas-ruled enclave.