Smoke billows from a Palestinian building following an Israeli air strike in Gaza City

AFP/Gaza

Fifty-one Gazans were killed on Friday as Israel pressed a major ground offensive in the coastal enclave, raising the overall Palestinian death toll since July 8 to 292, medics said.
An Israeli soldier was also killed as troops began an offensive on the Gaza periphery aimed at destroying Hamas's network of cross-border tunnels, the army said.
Israeli television said he died by "friendly fire".
The latest Palestinian deaths included three members of a family killed in an Israeli strike in southern Gaza's Rafah, as well as a 21-year-old man also killed in Rafah, emergency services spokesman Ashraf al-Qudra.
Witnesses said the 21-year-old was killed in the same air strike, but Qudra did not immediately confirm that.
Shortly before, eight members of a single family -- two men, two women and four children -- were killed in tank shelling on their home in northern Gaza's Beit Hanun.
Qudra gave the names of the children as Hania, Ahlam, Samih and Musa -- two girls and two boys.
And four children ranging in age from two to 13 years old were killed in tank shelling east of Gaza City, Qudra said.
Among them were brothers Emad Alwan, seven, and Qasem Alwan, four.
In the southern city of Rafah a man was killed by tank shelling, and in Khan Yunis, a 23-year-old died of wounds sustained earlier in the week.
The deaths raised the toll in Gaza during the 11 days of the conflict to 292, as Israel pressed a ground operation it announced on Thursday night.
Many of the deaths were in southern Khan Yunis and Rafah, where a five-month-old baby was among those killed.  
Figures provided by the Gaza-based Palestinian Centre for Human Rights show civilians account for more than 80 percent of the victims of Israel's assault since July 8 to halt rocket fire by militants of the Islamist movement Hamas which controls the coastal strip.
At least 2,200 Palestinians have also been wounded.
Since the Israeli operation began, more than 1,207 rockets fired from Gaza have struck Israel, and another 333 have been shot down by the country's Iron Dome air defence system, army figures show.
On the Israeli side, a civilian was killed by rocket fire earlier this week, while four others were seriously injured.