Judges at a UN-backed tribunal Wednesday threw out a bid to acquit an alleged Hezbollah member of any role in the 2005 assassination of ex-Lebanese prime minister Rafi Hariri.
The chamber at the Special Tribunal for Lebanon "finds that the prosecution has provided a sufficiency of evidence upon which it could convict" Hussein Oneissi, presiding judge David Re said.
"Application for his acquittal is therefore dismissed," Re added.
The judge stressed though the court "could still acquit Mr Oneissi at the end of the trial" if the prosecution has not proved the charges "beyond reasonable doubt".
The prosecution last month concluded its case against Oneissi, and three other suspected Hezbollah members, all being tried in absentia in the court in the Netherlands.
Before opening the defence case, lawyers for Oneissi, 44, had argued the five charges against him should be dropped as the prosecution had failed to provide sufficient evidence.
The judges agreed much of the evidence against Oneissi, much of which is based on records from mobile phone networks and SIM cards used in the attack, was circumstantial.
But "the number of coincidental actions is such that the trial chamber has sufficient evidence from which it could convict Mr Oneissi of his involvement in the attack on Mr Hariri," judge Janet Nosworthy said.
Hariri, who was Lebanon's Sunni Muslim prime minister until his resignation in October 2004, was killed in February 2005, when a suicide bomber detonated a van packed with tonnes of explosives next to his armoured convoy on the Beirut seafront.
Another 21 people were killed and 226 injured in the assassination, with fingers pointing at Syria which had long been a power-broker in the country.
"The assassination of Mr. Hariri was obviously a carefully planned and rehearsed event requiring ... military precision," said Re.
Oneissi is notably accused of having recruited Lebanese Islamist Ahmed Abu Adass, and helping him to make a videotape falsely claiming the assassination.
Within minutes of the attack, the false claim of responsibility was made in several phone calls to Reuters news agency. Shortly afterwards a videotape of Abu Adass's "confession" was dropped off in a tree by the Beirut offices of Al-Jazeera.
The court agreed that since the trial opened in January 2014 no evidence had been found that Abu Adass was the suicide bomber and his DNA had not been found at the scene.
Rather Abu Adass had been used as a decoy "to divert attention from the attackers" to a "fictional fundamentalist group", Nosworthy said.
Ayyash, as well as a fifth suspect Hezbollah commander Mustafa Badreddine, are accused of masterminding the plot, with Oneissi and the two others as accomplices.
The case against Badreddine was dropped after he was said to have been killed in fighting in Syria in 2016.