JERUSALEM - Israeli Defense Forces (IDF) on Friday ordered residents of Gaza City to evacuate to the southern area of the coastal enclave ahead of a possible Israeli ground offensive.

"The IDF calls for the evacuation of all civilians ... for their own safety and protection," read a statement issued Friday morning.

"You will be able to return to Gaza City only when another announcement permitting it is made," the statement said.

According to the IDF, Hamas militants are using underground tunnels in the city to hide.

Israel is believed to be preparing for a ground incursion on the Gaza Strip, according to media reports and analysis.

Since this round of attacks between Hamas and Israel began on Saturday, Israel has launched hundreds of airstrikes against targets in the Gaza Strip. So far more than 1,500 Palestinians and more than 1,300 Israelis have been killed.