The UN’s top chemical weapons investigator in Syria has called for a new investigation to determine who was responsible for the chemical weapons attacks that killed hundreds.

Ake Sellstrom said that if there was no accountability, “I will think it’s sad”.

He led a team that confirmed the use of chemical weapons in a major attack near Damascus on August 21, and their probable use in four other locations against civilians and soldiers.

His team’s mandate was to determine whether chemical weapons were used, but not to establish who was responsible.

His team gathered lots of facts but not enough to determine the guilty party

Sellstrom said using chemical weapons was “a hideous crime... so it’s logical that this should be followed up and brought to court somehow, or brought to a tribunal, or brought to something”.

He said his team gathered “lots of facts” but not enough to determine “the guilty party in this”.

To determine who used chemical weapons, a much broader investigation was needed, Sellstrom said.

He said last Friday that his team did not have the freedom of a police force in carrying out its investigation.

There were “a lot of other facts with the Syrian government, with the Opposition, with several capitals”, he said, citing possible information on transport of chemical weapons, on militias, and on conversations that may have been overheard and recorded as well as other intelligence.