Hundreds gathered near Beirut's port yesterday to mark four years since a catastrophic explosion devastated the capital and to demand accountability, with the spectre of war weighing over commemorations.Nobody has been held responsible for the August 4, 2020 blast — one of history's biggest non-nuclear explosions — which killed more than 220 people, injured at least 6,500 and devastated swathes of the capital.Demonstrators, some holding images of those killed, demanded justice and accountability at the march headed by victims' relatives, who have grouped together in their fight."Four years have passed and the criminals have not been arrested," said Viviane Haddad, who was injured in the blast."Where is the justice?" she asked.Housewife Sonia Audeh, 53, said: "We want to know who caused the explosion... who took our children, our young people." At 6:07pm (15:07 GMT), the time of the explosion, demonstrators held a moment of silence while ambulances and boats sounded their sirens.Authorities said the explosion was triggered by a fire in a warehouse where a stockpile of ammonium nitrate fertiliser had been haphazardly stored for years.French President Emmanuel Macron, who visited Beirut after the blast, yesterday on social media platform X emphasised "France's unswerving commitment" to Lebanon and its "demand for justice for all the victims".An investigation into the blast has stalled, mired in legal and political wrangling.Cecile Roukoz, a lawyer for the victims' families whose brother died in the explosion, listed in a speech the names of political and security officials who she said had hindered the investigation, calling on judges to "fulfil their duty".William Noun, whose brother was killed in the blast, accused Lebanon's powerful Hezbollah group of blocking the inquiry and of threatening the investigating judge.In December 2020, lead investigator Fadi Sawan charged former prime minister Hassan Diab and three ex-ministers with negligence, but as political pressure mounted, he was removed from the case.His successor, Tarek Bitar, unsuccessfully asked lawmakers to lift parliamentary immunity for members of parliament who were formerly cabinet ministers.In December 2021, Bitar suspended his probe after a barrage of lawsuits, while Hezbollah has accused him of bias and demanded his dismissal.But in January last year, he resumed investigations, charging eight new suspects including high-level security officials and Lebanon's top prosecutor, who in turn charged Bitar with "usurping power" and ordered the release of detainees in the case.The process has since stalled again.###A judicial official, speaking on condition of anonymity, told AFP that Bitar would "resume his proceedings, starting next week" and intends to finish "the investigation and issue his indictment decision... by the end of the year".Bitar will set dates for questioning defendants who have not yet appeared before him, according to the official.If the public prosecutor's office or other relevant judicial officials fail to cooperate, Bitar "will issue arrest warrants in absentia" for the defendants, the official added.Activists have called for a UN fact-finding mission into the blast but Lebanese officials have repeatedly rejected the demand."The complete lack of accountability for such a man-made disaster is staggering," UN Special Coordinator for Lebanon Jeanine Hennis-Plasschaert said in a statement on Saturday."One would expect the concerned authorities to work tirelessly to lift all barriers... but the opposite is happening," she said, calling for "an impartial, thorough, and transparent investigation to deliver truth, justice, and accountability".Prospects of further disaster loom over this year's anniversary, with Hamas ally Hezbollah and the Israeli army trading cross-border fire since the Palestinian group's October 7 attack that triggered war in Gaza, and escalating fears that an all-out conflict could engulf Lebanon.