Tampering of Syria 'gas attack' evidence by Russia 'a possibility', says UN ambassador

There is a "possibility" that Russia has tampered with evidence of an alleged chemical weapons attack in Douma, the trigger for US, UK and French air strikes in Syria, the British ambassador to the UN said.

Karen Pierce said all the facts had not yet been established after the April 7 attack and said Russia and Syria should allow inspectors to visit the site.