Emergency medical aid and pop-up field hospitals were dispatched to Lebanon Wednesday along with rescue experts and tracking dogs, as the world reached out to the victims of the explosion that devastated Beirut.
The blast centred on the city's port caused massive destruction and killed at least 113 people, heaping misery on a country already in crisis.
Gulf states were among the first to respond, with Qatar sending mobile hospitals to ease pressure on Lebanon's medical system, already strained by the coronavirus pandemic.
A Qatari air force plane with a cargo of hundreds of collapsible beds, generators and burn sheets touched down in Beirut in the first of a convoy of flights to the Mediterranean country.
Medical supplies from Kuwait also arrived, as the Lebanese Red Cross said more than 4,000 people were being treated for injuries after the explosion, which sent glass shards and debris flying.
A Greek C-130 army transport plane bearing a dozen rescuers landed at Beirut's airport, itself damaged in the catastrophic explosion.
Lebanon's Prime Minister Hassan Diab has called on "friendly countries" to support a nation already reeling from its worst economic crisis in decades as well as the impact of the coronavirus.
As emergency crews hauled survivors from the rubble of demolished buildings, France said it was sending search and rescue experts aboard three military planes loaded with a mobile clinic and tonnes of medical and sanitary supplies.
President Emmanuel Macron is to travel to Lebanon on Thursday, becoming the first world leader to visit Beirut after the disaster, as France seeks to swiftly push reconstruction in its former colony.
"France is at the side of Lebanon. Always," Macron tweeted in Arabic.
Cyprus -- which lies just 150 miles (240 kilometres) to the northwest and where Tuesday's blast were both heard and sighted -- said it was sending eight police tracking dogs and their handlers aboard two helicopters, to help in the search for victims trapped under rubble.
Tunisia offered to send medical teams to collect 100 wounded people and evacuate them for treatment, as well as sending in two military transporters carrying food and medical aid.
From Europe, authorities in the Netherlands, Czech Republic and Poland offered an array of assistance including doctors, police and firefighters, together with rescue experts and sniffer dogs.
Iran's President Hassan Rouhani said Tehran stood "ready to offer medical and medicinal aid and help treat the injured", and Jordan's King Abdullah II also promised to dispatch a field hospital.
The United Arab Emirates sent 30 tonnes of medicines, medical supplies and surgical equipment.
- 'Stay strong, Lebanon' -
The World Health Organization said it was dispatching trauma and surgical kits from its base in Dubai after what it called a "shocking event" that comes at a "particularly difficult time in Lebanon".
"As you've seen, many hospitals are overwhelmed with casualties and people are still looking for the injured and the dead, so it's a very sad day," the UN agency's emergencies director Michael Ryan told an online session.
Close allies and traditional adversaries of Lebanon alike sent their condolences, with Iran and Saudi Arabia -- long rivals for influence over the country -- both sending messages of support.
"Our thoughts and prayers are with the great and resilient people of Lebanon," Iranian Foreign Minister Mohammad Javad Zarif tweeted.
"Stay strong, Lebanon."
Saudi Arabia said it was following the situation with "great concern".
Unusually, neighbouring Israel offered humanitarian aid -- to a country with which it is still technically at war -- via international intermediaries.
Lebanon's flag was to be projected onto Tel Aviv's city hall later Wednesday, in Israel's latest gesture.
United Nations chief Antonio Guterres expressed his "deepest condolences... following the horrific explosions in Beirut," which also injured some UN personnel.
US President Donald Trump, who said it looked like "a terrible attack", without giving any evidence, said: "Our prayers go out to all the victims and their families... The United States stands ready to assist Lebanon."
British Prime Minister Boris Johnson called the pictures and videos from Beirut "shocking".
And Pope Francis offered prayers for the victims and their families so that they might "face this extremely tragic and painful moment and, with the help of the international community, overcome the grave crisis they are experiencing".