Smoke rises from an explosion site at the port of Beirut, Lebanon, Aug. 4, 2020. The two huge explosions that rocked Lebanon's capital Beirut on Tuesday left dozens dead and injured, al-Jadeed TV channel reported.(Xinhua/Bilal Jawich)

Two huge explosions rocked Lebanese capital Beirut on Tuesday, leaving at least 73 people dead and 3,000 others injured.

The blasts hit the Port of Beirut at around 6:10 p.m. local time (1610 GMT), shaking buildings all over the city while causing massive casualties and damage.

The number of casualties is expected to rise as the counting continues. Local media outlets have been announcing the names of hundreds of people still missing, in the hope of helping their families find them.

The causes of the blasts remain unknown, but Lebanese Interior Minister Mohammad Fahmi said the explosive chemicals stored at Port of Beirut may have led to the explosions.

"Customs authorities must be asked about the reasons behind storing such chemical materials at Port of Beirut," Fahmi said.

Investigations into the explosions are expected to reveal the real causes of the disaster within five days.

Following the explosions, Lebanese Prime Minister Hassan Diab immediately declared Wednesday a national mourning day for the victims of the explosions.

Meanwhile, Diab urged friendly countries to help Lebanon overcome the repercussions of the disastrous explosions.

Lebanese President Michel Aoun also called an emergency meeting of the Higher Defense Council, which later on Tuesday declared Beirut as an afflicted city while urging the Lebanese cabinet to announce a state of emergency in the city for two weeks.

The council also urged the cabinet to allocate funds for hospitals to help them treat the injured, and to contact all friendly countries to seek support and set up a fund to provide compensations for those affected by the disaster.

It recommended hosting the families whose houses were destroyed in schools, while importing glass and controlling the prices of all materials needed to fix the damaged houses.

During the meeting, Diab insisted that those responsible for the disaster be punished, noting that it is unacceptable to store 2,700 tons of ammonium nitrate, the explosive chemicals, which have put people's lives at great risk.

The Lebanese cabinet is expected to hold a meeting on Wednesday to look into the proposal by the Higher Defense Council and announce new measures to deal with the current crisis.

Many countries have expressed solidarity and sympathy with Lebanon over the explosions that have dealt a further blow to the country already plagued by the COVID-19 pandemic and an economic crisis.

The Al-Jadeed TV reported that Iraq and Qatar will send field hospitals to Lebanon on Wednesday, while French President Emmanuel Macron, in a phone call with Aoun, promised to send support for Lebanon on Wednesday.

Iranian Foreign Minister Mohammad Javad Zarif said on Tuesday via his official Twitter account that Iran is ready to offer help to Lebanon.

"Our thoughts and prayers are with the great and resilient people of Lebanon," Zarif tweeted. "As always, Iran is fully prepared to render assistance in any way necessary."

"Stay strong, Lebanon," he added.

Iran's Foreign Ministry spokesman Abbas Mousavi also expressed sympathy with the Lebanese government and people over the incident, while announcing Iran's readiness for providing help to the Arab country.

Iran is following the news on the incident with "deep grief" and "expresses solidarity with the Lebanese nation and government at this difficult time," Mousavi said in a statement.

The Turkish Foreign Ministry on Tuesday expressed sorrow over the massive casualties and damages caused by the huge explosions, during which two Turkish citizens were slightly injured.

"We wish God's mercy on those who lost their lives in this incident, urgent healing to those who were injured, and condolences to the Lebanese people, friends and brothers," the ministry said in a written statement.

Egyptian President Abdel-Fattah al-Sisi extended his condolences to Lebanon over the deadly explosions, and wished speedy recovery for those injured in the blasts.

"My sincere condolences and sympathy go to the government and people of Lebanon, over the tragic explosions that happened today in the Lebanese capital Beirut," Sisi wrote on his official Facebook page.

Palestinian President Mahmoud Abbas said on Tuesday that his country is ready to provide any support it could to Lebanon to help it recover from the tragedy, while sending his condolences to the families of the victims.

Palestinian Prime Minister Mohammed Ishtaye said in a press statement that Palestine is "ready to put all its capabilities" for the service of Lebanon and provide any needed assistance immediately.

Member of the Palestine Liberation Organization's Executive Committee Hanan Ashrawi also expressed sorrow over the "devastating tragedy" and her wishes for Beirut to overcome the calamity.

In the Gaza Strip, Ismail Haniyeh, head of the Islamic Hamas movement, phoned President Aoun to express his support for Lebanon amidst the grave situation.

In a rare move, Israel on Tuesday offered humanitarian aid to Lebanon over the explosions.

"Israel addressed Lebanon through international security and political elements and offered the Lebanese government medical humanitarian assistance," Israel's Foreign Ministry and Defense Ministry said in a joint statement.

Israel and Lebanon have no official ties and tensions have been rising on the Israel-Lebanon border recently.