Israel carried out air strikes on the Gaza Strip overnight Monday, sources from both sides said, in what Israel said was a response to recent rocket fire against the Jewish state.

Israeli planes targetted an arms factory in the centre of the Palestinian territory as well as three tunnels used for smuggling contraband, two in the north and one in the south, the army said in a statement.

The targets were hit, the statement added.

"The targetting of these sites was in response to rockets fired against Israel in recent days," the military said.

A security source from the Islamist Hamas movement, which controls the territory, and witnesses said there were four strikes -- in Beit Lahiya, Nuseirat and two in Khan Yunis.

There were no casualties in the attack, the Hamas source said.

So far this month at least eight rockets have been fired towards Israeli territory from the Palestinian enclave controlled by the Islamist Hamas movement.

They resulted in no injuries or major damage.

Hamas has engaged in a tacit truce with Israel, secured with Egyptian mediation, but that has not stopped more radical organisation, notably among Gaza's Salafist minority, from firing projectiles into southern Israel.

Four Palestinian fighters have been killed by Israeli strikes since the end of December.