Former brigadier general Mohammed Hamo, 65, who lives in Sweden and was one of the highest-ranking Syrian military officials to have been tried in Europe, stood accused of "aiding and abetting" war crimes in the first half of 2012.

In a statement announcing its verdict, the Stockholm district court said that while the Syrian military had used "indiscriminate attacks" at that time, the prosecution did not prove that Hamo's division was involved in those attacks, or that he had a role in providing arms for the assaults.

In his role as brigadier general and head of the 11th division's armament unit, the prosecution had argued that Hamo allegedly helped coordinate the supply of arms and ammunition to units involved in such attacks near the towns of Homs and Hama.

"The main issues in the case are whether the 11th Division of the Syrian Army participated in indiscriminate attacks in certain areas and whether the defendant participated in arming the division in those attacks," judge Katarina Fabian wrote.

- Not sufficient -

"According to the District Court, there is no evidence to clarify these issues. The evidence presented by the prosecution has therefore not been deemed sufficient to convict the defendant of a criminal offence," Fabian said.

The war between President Bashar al-Assad's regime and armed opposition groups, including Islamic State, erupted after the government repressed peaceful pro-democracy protests in 2011.

It has killed more than half a million people, displaced millions, and ravaged Syria's economy and infrastructure.

The prosecution argued that the Syrian army's "widespread air and ground attacks" caused damage "at a scale that was disproportionate in view of the concrete and immediate general military advantages that could be expected to be achieved".

Hamo denied criminal responsibility and his lawyer, Mari Kilman, told the court the officer could not be held liable for the actions "as he had acted in a military context and had to follow orders."

- First of its kind -

"What is noteworthy about this case is that this is the first trial concerning the Syrian military's warfare. That is, how the warfare was carried out," said Aida Samani, senior legal advisor at rights group Civil Rights Defenders, which has been monitoring the trial.

No European court has previously dealt with this issue and the impact on civilian lives and infrastructure, she added.

Hamo is the highest-ranking military official to go on trial in Europe in person, though other countries have tried to bring charges against more senior members.

In March, Swiss prosecutors charged Rifaat al-Assad, an uncle of President Bashar al-Assad, with war crimes and crimes against humanity.

However, it remains unlikely Rifaat al-Assad -- who recently returned to Syria after 37 years in exile -- will show up for the trial, for which a date has yet to be set.

Swiss law allows for trials in absentia under certain conditions.

In November, France issued an international arrest warrant for Bashar al-Assad, accusing him of complicity in crimes against humanity and war crimes over chemical attacks in 2013.

Three other international warrants were also issued for the arrests of Bashar al-Assad's brother Maher, the de-facto chief of the army's elite Fourth Division, and two generals.

In May, a Paris court also ordered life prison sentences for three top Syrian security officials for complicity in crimes against humanity and war crimes.

The accused -- Ali Mamlouk, former head of the National Security Bureau; Jamil Hassan, former director of the Air Force intelligence service; and Abdel Salam Mahmoud, former head of investigations -- were all tried in absentia, but there are international warrants for their arrest.

In January 2022, a German court sentenced former colonel Anwar Raslan to life in jail for crimes against humanity. That was the first international trial over state-sponsored torture in Syria and was hailed by victims as a victory for justice.