ISRAELI air strikes on central and southern Gaza have killed four people with Palestinian security sources confirming at least three of them were militants.

Saturday's deaths raised the overall death toll in Gaza to 34 as a relentless Israeli air campaign against Gaza militants entered its fourth straight day.

"Three men died in an Israeli air strike on Maghazi camp in central Gaza," said emergency services spokesman Adham Abu Selmiya.

Separately, medics said another person was killed in a strike on a motorcycle in the Tel al-Sultan neighbourhood of the southern city of Rafah, which took place shortly before a visit by Tunisian Foreign Minister Rafik Abdessalem

He was, who is expected to arrive through the Rafah border crossing with Egypt at around 1900 (AEDT) official sources said.

A Palestinian security source told AFP the three who died in central Gaza were all militants from the armed wing of the ruling Hamas movement, the Ezzedine al-Qassam Brigades, naming them as Ali Manameh, Hossam Abdel Jawad and Assaf Gharwish.

Originally published as Fresh Israeli strike kills four in Gaza