Israeli navy commandos made the first ground incursion into the Gaza Strip early on Sunday to carry out a raid on a missile launch site, Israel Defense Forces said.

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The mission was accomplished, IDF said.

1/2 BREAKING: IDF forces raided a site used to fire long-range rockets at Israel. The mission was accomplished — IDF (@IDFSpokesperson) July 13, 2014

Four Israeli soldiers were slightly injured in the exchange of fire that took place during the operation.

"The IDF will continue to harm any element which uses terror against Israel," IDF spokesperson stated in a statement.

Hamas said its fighters had fired at the Israeli force offshore and claimed that they prevented it from landing, Reuters reported.

This comes as Israel’s Operation Protective Edge enters its sixth day. Israeli airstrikes on Gaza killed 52 people on Saturday, making it the deadliest day of the offensive. Among the dead were two severely handicapped women in a care facility, AFP cited medics as saying. The total Palestinian death toll now stands at 157.

Read more: Israeli airstrike hits home of Gaza police chief, death toll continues to rise

Israel is keeping the option of a ground invasion open, with about 20,000 reservists mobilized.

Meanwhile the UN Security Council called for a ceasefire between Israel and Palestine on Saturday, citing serious concerns about the protection of civilians on both sides.

"The Security Council members called for de-escalation of the situation, restoration of calm, and reinstitution of the November 2012 ceasefire," the 15-member body said in a statement.

But Israel said that a truce is not in the cards as long as Hamas continues to fire rockets.