The head of Lebanon's Iran-backed Hezbollah group warned Israel Friday that it will respond swiftly "on the battlefield" to the killing of Hamas's deputy leader in its south Beirut stronghold.

"The response is inevitably coming. We cannot remain silent on a violation of this magnitude because it means the whole of Lebanon would be exposed," Hassan Nasrallah said in a televised speech.

"The decision is now in the hands of the battlefield," he said in his second speech since the killing of Saleh al-Aruri on Tuesday.

Shipping giant Maersk said Friday that it would divert all vessels around Africa instead of using the Red Sea and Suez Canal for the "foreseeable future" after Yemeni rebels attacked its merchant ships.

The Danish company cited the highly volatile situation and noted that the security risk remains high.

"We have therefore decided that all Maersk vessels due to transit the Red Sea/Gulf of Aden will be diverted south around the Cape of Good Hope for the foreseeable future," it said in a statement.

Iranian President Ebrahim Raisi joined mourners in the southern city of Kerman on Friday for the funerals of 89 people killed in twin blasts claimed by the Islamic State group, state media reported.

Suicide bombers struck crowds gathered near the tomb of storied Revolutionary Guards general Qasem Soleimani to mark the fourth anniversary of his killing in Baghdad in a targeted US drone strike.

The attack killed 89 people, who included many women and children as well as at least a dozen Afghans, state television said.

India's navy said Friday it had rescued 21 crew members from a vessel in the Arabian Sea after a hijacking distress call, the latest attack on commercial shipping in the region.

Last month the force deployed several warships into the sea to "maintain a deterrent presence" after a string of recent shipping attacks, including a drone strike near India's coast which the United States has blamed on Iran.

Bombing continued across Gaza on Friday as the United Nations warned Israel's war with militant group Hamas, now approaching its fourth month, had made the territory "uninhabitable".

With much of the Gaza Strip already reduced to rubble, air strikes hit the southern cities of Khan Yunis and Rafah as well as parts of central Gaza, AFP correspondents reported.

The Israeli army said its forces had "struck over 100 targets" across Gaza over the previous 24 hours, including military positions, rocket launch sites and weapons depots.

US Secretary of State Antony Blinken arrived in Turkey on Friday to start his fourth Middle East crisis tour since the start of the Israel-Hamas war three months ago.

The top American diplomat will visit Israel, the Palestinian Authority base in the West Bank and five Arab countries -- Egypt, Jordan, Qatar, Saudi Arabia and the United Arab Emirates, the State Department said.

The Islamic State jihadist group said Thursday that it carried out twin bombings which killed 84 people in Iran, but its claim is unlikely to entirely silence those who see an Israeli hand amid its war with Iran ally Hamas.

Labelled a "terrorist attack" by Iranian authorities, Wednesday's bombings hit crowds commemorating Revolutionary Guards general Qasem Soleimani, four years after his death in a US drone strike.

More than a thousand mourners attended the funeral in Beirut on Thursday of Hamas number two Saleh al-Aruri who was killed in a Lebanon strike blamed on Israel.

Calling on Hamas to avenge his death and the killing of five other members of the Palestinian militant group on Tuesday, the mourners gathered at a mosque to recite the prayer of the dead before marching to Shatila refugee camp where three of them were buried.

A US strike in Baghdad on Thursday killed a pro-Iran military commander, the Pentagon said, with Al-Hashed al-Shaabi ex-paramilitaries saying it hit one of their headquarters.

An Iraqi security official said two people were killed and seven wounded in the drone strike, which the government dubbed a "blatant aggression".

But Pentagon spokesman Major General Pat Ryder said the strike was an act of self-defence against a commander who was actively planning attacks against US personnel.

A "US strike" in Baghdad on Thursday killed a military commander of the Hashed al-Shaabi, an ex-paramilitary faction of the grouping said, with an Iraqi security official reporting two deaths in a drone attack.

The Iraqi government, supported by pro-Tehran factions, decried an "aggression". It accused a US-led international coalition but stopped short of pinning the blame on Washington, as regional tensions soar amid the Israel-Hamas war.