The Israeli army reported on Saturday evening a rocket had been fired from the Gaza Strip towards Israel, the first in a month.

The attack came as one of Gaza's larger armed factions, Islamic Jihad, threatened to retaliate after Israeli troops killed two of its leaders in the West Bank town of Jenin on Thursday.

"In response to the rocket fired toward Israeli territory, IDF fighter jets targeted overnight (Sunday) a weapons manufacturing site belonging to the Hamas terrorist organisation," the Israeli army said in a statement.

The target was a site "where the majority of the organisation's rockets in the Gaza Strip are being manufactured", it said.

Israel Defense Forces also hit "a Hamas terrorist tunnel in the Southern Gaza Strip", it said.

Security sources in Gaza reported two strikes in the south of the enclave, one against a military training site in Khan Younis and the other in an uninhabited area close to Rafah.

The strikes caused no injuries, according to Palestinian medical sources.

In August, at least 49 Palestinians, including combatants but also civilians, were killed in three days of fighting between Israel and Palestinian militants in Gaza, which has been under Israeli blockade since 2007.