Story highlights UK scientists conducted tests in British labs

Turkey Health Minister 'certain' Sarin used in attack

London (CNN) British scientists have tested samples from victims of last week's chemical attack in Syria and claim to have evidence that Sarin gas, or a similar substance, was used in the bombing.

A Ministry of Defense spokesperson told CNN on Thursday that the scientists had conducted the tests in British labs on blood and hair samples from victims, collected at Khan Sheikhun in Syria's idlib province, where 89 people were killed in the April 4 gas attack.

"These have tested positive for the nerve agent Sarin, or a Sarin-like substance," the spokesperson said.

The spokesperson did not say how the samples had reached the United Kingdom but explained that Britain chose to carry out its own analysis and was not working on behalf of any other country or body.

The tests were not part of an official investigation launched by the Organization for the Prohibition of Chemical Weapons in the wake of the attack.

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