More than 80 Palestinians have died since Israel launched air attacks on Hamas group in the Gaza Strip on Tuesday, the country's Health Ministry said.
According to Palestinian hospital officials, half of those killed were women and children.
The Israeli forces have stepped up air raids on Gaza on Thursday. Two strikes killed 16 people, and demolished two homes and a beachside cafe, reported the Guardian.
Israeli military spokesman lieutenant colonel Peter Lerner said that the country had struck more than 320 Hamas targets overnight bringing the total number of hits in the last three days to over 750.
The country has mobilised 20,000 reservists for a possible ground operation in Gaza but that would be the last option, Lerner added.
Israel Prime Minister Benjamin Netanyahu discussed the course of action with his officials and hinted at ground attack, reported Reuters.
"So far the battle is progressing as planned but we can expect further stages in future. Up to now, we have hit Hamas and the terror organisations hard and as the battle continues we will increase strikes at them," Netanyahu said in a televised statement.
The Hamas has also increased rockets attacks on Israel, launching 100 on Thursday alone.
The Israeli military said that the Hamas militants have fired over 440 projectiles since 8 July, but there were no serious casualties.
Meanwhile, US President Barack Obama has offered to negotiate a ceasefire.
The White House said in a statement: "The US remains prepared to facilitate a cessation of hostilities, including a return to the November 2012 ceasefire agreement."
International leaders, including French and Russian Presidents Francois Hollande and Vladimir Putin also made ceasefire pleas, reported BBC.