An Israeli army statement said "several terrorists were injured" in an explosion as they attempted to carry out sabotage near the border fence, but made no mention of troops opening fire.

Gaza's health ministry said "Sabri Ahmed Abu Khader, 24, was killed by bullets of the (Israeli) occupation forces", without giving further details.

At least 131 Palestinians have been killed by Israeli fire since major border protests broke out at the end of March.

No Israelis have been killed.

Palestinians are demanding the right to return to the homes their families fled or were expelled from during the 1948 war surrounding the creation of Israel.

The Gaza Strip is controlled by the Islamist movement Hamas which Israel considers its bitter enemy.

The two sides have fought three wars since 2008 and observe a tense ceasefire.

The Israeli army said Monday that five "terrorists" had "attempted to sabotage a security infrastructure in the area of the barrier in the northern Gaza Strip".

"The security infrastructure exploded," it said in an English-language statement. "Subsequently, several terrorists were injured."

Earlier, Israeli warplanes conducted strikes against nine Hamas "military targets" in northern Gaza in response to incendiary kites and balloons being sent into Israeli territory, the army said.

The attacks targeted two Hamas military sites and a munitions manufacturing site, the military said in a statement, without specifying whether the raids had resulted in casualties.

Israeli Defence Minister Avigdor Lieberman warned after Monday's strikes that Gazans would pay a price for the fire attacks.

"If anyone thinks they can continue the routine of kites and fires every day - he's mistaken.," his office quoted him as saying.

Palestinian security sources said nobody was wounded in the morning air strikes.

"Fire balloons" and kites carrying flammable material have become symbols of the Palestinian border protests in recent months.

Lieberman says that 400 kites have been intercepted out of some 600 launched since the end of March.

So far more than 300 fires have devastated several thousand hectares (acres) of fields and shrubland, according to the Israeli fire service.