Palestinian medical officials say Israeli airstrikes on the Gaza Strip have killed one Palestinian and injured at least 20 other people.

Officials say a six-year-old boy was killed in a strike Saturday near the town of Khan Younis.

Israel has denied any involvement in the child's death.

Authorities say the Israeli strikes were in retaliation for rockets fired earlier Saturday by Palestinian militants. One of the rockets hit the Israeli town of Sderot, injuring an Israeli man.

The violence erupted despite a shaky Egyptian-brokered truce between Israel and the militant group Hamas, which is the elected ruling party in the Gaza Strip. The truce was announced Wednesday and had temporarily calmed violence that erupted on Monday following a raid across Egypt's Sinai border.