Palestinian paramedics carry a wounded protester during clashes with Israeli forces in the eastern Gaza Strip. Mahmud Hams/AFP

Three Palestinians were killed by Israeli soldiers in the northern Gaza Strip, the Palestinian health ministry said on Sunday.

The ministry said another Palestinian was hospitalised in the shooting that came after the Israeli army said an attack helicopter and tank had fired at "armed suspects" along the barrier that separates Israel from Gaza.

A Palestinian protester uses a slingshot near the fence along the border with Israel in the eastern Gaza Strip. Mahmud Hams/AFP

"We just identified a number of armed suspects from Gaza approaching the security fence with Israel. We fired towards them," the army said a statement posted on its Twitter account.

The latest violence came after Palestinians in the Hamas-ruled Gaza Strip fired three rockets at southern Israel late Saturday, the Israeli army said, in the second such attack in 24 hours.

There were no immediate reports of casualties.

The army said two of the projectiles had been intercepted by its Iron Dome aerial defence system but it did not specify what happened to the third rocket.

On Friday Palestinians in Gaza fired a rocket at Sderot, in what the army said was the first such attack since July 12.

In response, Israeli warplanes struck at least three targets in the Gaza Strip early on Saturday but caused no casualties, a Palestinian security source said.

The strikes hit a Hamas observation post in Beit Hanoun, in the northern Gaza Strip, an unidentified target near Gaza City and open ground near Deir El Balah in the central part of the territory, the source said.

Agence France-Presse