BEIRUT: Rescue teams were still searching the rubble of Beirut's port for bodies on Friday, nearly three days after a massive explosion sent a wave of destruction through Lebanon's capital, killing nearly 150 people and wounding thousands. At least four more bodies have been recovered in the last 24 hours, and authorities say the death toll has risen to 149. The blast shredded a large grain silo, devastated neighbourhoods near the port and left several city blocks littered with glass and rubble. French and Russian rescue teams with dogs were searching the port area on Friday, the day after French President Emmanuel Macron paid a visit to the site, promising aid while demanding reform from Lebanon's long-entrenched political leaders. The blast was apparently caused by the ignition of 2,750 tons of ammonium nitrate, a chemical used for explosives and fertilizer, that had been stored at the port since it was confiscated from an impounded cargo ship in 2013. The government has launched an investigation as it has come under mounting criticism, with many Lebanese blaming the catastrophe on negligence and corruption. Search and rescue teams have been sent from several countries to help locate survivors of the blast. Among those located in the rubble near the grain silo was Joe Akiki, a 23-year-old port worker who had been missing since the explosion. A team of 55 French rescuers that began work Thursday has found four bodies, according to Col. Tissier Vincent, the head of the mission. Lebanese firefighters are also working at the demolished port, where bulldozers and excavators were churning through the rubble. Dozens of people are still missing, and at the entrance to the port a family waited for news of a relative. Some 300,000 people — more than 12% of Beirut's population — are unable to return to their homes because of the explosion, which blew out doors and windows across the city and left many buildings uninhabitable. Officials have estimated losses at $10 billion to $15 billion. Damaged hospitals, already strained by the coronavirus pandemic, are still struggling to deal with the wounded. The investigation is focusing on port and customs officials, with 16 employees detained and others questioned. But many Lebanese say it points to much greater rot that permeates the political system and extends to the country's top leadership. For decades, Lebanon has been dominated by the same political elites — many of them former warlords and militia commanders from the 1975-1990 civil war. The ruling factions use public institutions to accumulate wealth and distribute patronage to supporters. Thirty years after the end of the civil war, power outages are still frequent, trash often goes uncollected and tap water is largely undrinkable. Even before the blast, the country was mired in a severe economic crisis that was also widely blamed on the political class. Unemployment was soaring, and a collapse of the local currency wiped out many people's savings, That will make the task of rebuilding after the blast even more daunting. Macron said France would lead international efforts to provide aid but would not give 'blank checks to a system that no longer has the trust of its people.' France, which has close ties to its former colony, has also sent a team of 22 investigators to help probe the blast. Based on information from Lebanon so far, France's No. 2 forensic police official, Dominique Abbenanti, said Friday the explosion 'appears to be an accident' but that it's too early to say for sure. In an interview with The Associated Press, he predicted 'the death toll will grow' as more bodies are found. French investigators are involved at the request of Lebanon, and also because one French person died and at least 40 were injured in the massive blast. French police could later question witnesses or suspects, said Eric Berot, chief of a unit involved in the investigation. For now, the French team is dividing up zones to cover with Lebanese counterparts and will use drones to study the area. 'The zone is enormous. It's a titanic job,' Berot said. The investigation is complicated by the huge scale of the damage and 'the Lebanese situation,' he said, referring to the political and economic crisis in the country. The U.N. human rights office meanwhile called for an independent investigation, insisting 'victims'' calls for accountability must be heard.' Rupert Colville, a spokesman for the U.N. High Commissioner for Human Rights, cited the need for the international community to 'step up' to help Lebanon with both a quick response and sustained engagement. He said Lebanon is facing the 'triple tragedy of the socio-economic crisis, COVID-19 and the ammonium nitrate explosion.' Colville urged Lebanese leaders to 'overcome political stalemates and address the grievances of the population.'