Two men arrested under the Terrorism Act 2006 when police discovered two large containers marked 'hydrogen peroxide' in a Bristol flat were released without charge today after a Home Office scientist confirmed that it was in fact vegetable oil.

The discovery was made on Wednesday evening after a man was arrested in the Castle Park area of the city on suspicion of drug-related offences.

Police then searched another address in the Easton area and found the two 25 litre containers that led them to believe there may be a potential link to terrorist activity, a spokesman for Avon and Somerset Police said. A second man was then arrested.

"There is a heightened vigilance with the general terrorist threat and that has sparked our inquiry as to why someone would ostensibly be in possession of up to 50 litres of hydrogen peroxide,” Steve Mortimore, Assistant Chief Constable of Avon and Somerset Constabulary, said after the arrests.

“If it turns out to be 50 litres of industrial strength hydrogen peroxide, then clearly there are some questions to answer. We’ve got one man from Afghanistan and one man from Somalia," he added.

But after forensic tests, the force announced this evening that the substance was not hyrdorgen peroxide - which can be used to make explosives - but "an oil-based liquid that was not dangerous".

The two men - one in his 20s originally from Afghanistan and a Somalian in his early 50s - were released without charge.

"I am satisfied that the police response to this incident was entirely appropriate in all the circumstances," Mr Mortimore said tonight.

"When we found two containers labelled with hydrogen peroxide, we clearly had to take that very seriously, and an intensive operation began to try to establish exactly what we were dealing with.

"As recent events in London and Glasgow demonstrated, the terrorist threat in the UK is very real, and it is important that every one remains alert to that threat.

"I hope that the public will be reassured that Avon and Somerset Police is vigilant to the threat, and that the force is ready and able to act swiftly and effectively if any potential terrorist risk comes to light.

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