israeli soldier beach
Hamas claims to have captured an Israeli soldier as fighting continues in Gaza. AFP

A spokesman for Hamas' armed wing has claimed the group captured an Israeli soldier during fighting in the Gaza Strip.

Speaking on a Hamas television station, a masked spokesman named Abu Ubaida, said: "We have captured a Zionist soldier and the occupation has not admitted that."

It is believed the soldier was captured during an assault on the Gaza Strip that has left at least 100 Palestinians dead.

Israel has yet to comment on the claim.

The latest report comes after 13 Israeli soldiers were killed during the country's ground offensive in Gaza in the deadliest day of the ongoing conflict between Israel and Hamas.

According to the Israeli military, the 13 soldiers, from Golani brigade, died during the offensive on Sunday. Seven were killed after their armoured personnel carrier was hit by an anti-tank missile.

The ambush, in the dense urban environment of Gaza City, was accompanied by machine gun fire and further casualties occurred in the aftermath of the blast.

We got to get over there ... we ought to go tonight. I think it's crazy to be sitting around.
- John Kerry, US Secretary of State

The northeast Gazan neighbourhood of Shaja'iya was also the scene of a massacre following intense shelling which left many dead, including women and children.

35,000 people are reported to have fled the region after the artillery bombardment began. Eye witnesses have described a scene of carnage with people leaving their homes and belongings behind and "literally running for their lives."

Naftali Bennett, Israel's economic minister, claimed that Hamas was "cynically" using women and children as human shields.

"They only difference between us and Hamas in Gaza is that they are deliberately sending their women and children to stand next to missile launchers in order for them to get killed and then they cry to the world that they are being killed," he said.

The Israeli military has defended their bombardment of the neighbourhood, stating that it had sent recorded evacuation warnings to residents two days prior as it sought to target Hamas command centres in the area.

Israel's Prime Minister Bejamin Netanyahu has vowed to continue the military incursion to secure the safety of those living in the south of the country.

Speaking at a press conference, Mr Netanyahu said: "We are carrying out a complex, deep, intensive activity inside the Gaza Strip and there is world support for this ... very strong support within the international community for the activity that the IDF (Israeli Defence Forces) is doing."

In a telephone call with Mr Netanyahu, US President Barack Obama expressed serious concerns about the rising number of casualties "and stressed the need to protect civilians-in Gaza and in Israel".

US Secretary of State John Kerry, who is expected to travel to the Middle East to press for a ceasefire was overheard saying to an aide: "We got to get over there ... we ought to go tonight. I think it's crazy to be sitting around."

UN Secretary-General Ban Ki-moon has travelled to Qatar to try to restart ceasefire efforts.

According to the Gaza Health Ministry, more than 425 Palestinians have been killed and more than 2,600 wounded, since the start of the fighting.

A total of 18 Israeli military personnel have been killed and two Israeli civilians have also died in rocket attacks.