Six people from a same family were killed and five others injured in an airstrike on their home in Rafah City, Xinhua reported citing the medics.
The situation in Gaza has dramatically worsened hours after a 72-hour UN-backed ceasefire came into force as Israeli artillery fire pounded Rafah City, killing and injuring dozens Palestinians.
Israel said the bombardment came after Hamas breached the ceasefire deal by carrying out attack against Israeli soldiers near Gaza.
More than 1,620 Palestinians have been killed and some 8,700 people have been injured since Israel stepped up an offensive Gaza on July 8.
On the Israel side, 61 soldiers and three civilians were killed.