Police have admitted that liquid found in two 25-litre containers in Bristol is oil and not, as previously said, hydrogen peroxide.

Two men initially arrested under terrorism legislation – a man from Afghanistan in his 20s and a Somalian man in his early 50s – have been released without charge.

Avon and Somerset police discovered the containers following a house search in Stapleton Road after one of the two men detained under terror laws was arrested on suspected drug offences.

But after a forensic analysis by a Home Office scientist, it was revealed that a "non-hazardous" oil substance was contained within them.

"Investigations are still taking place to ascertain how those containers came to be at that location and where they had come from," a police statement said.

Despite the confusion, Avon and Somerset constabulary's Assistant Chief Constable Steve Mortimore said that the police response had been "entirely appropriate in all the circumstances".

"I am sure that many people were very concerned when they became aware that two people had been arrested in Bristol under terrorism legislation – and that is quite understandable," he said in a statement.

"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 everyone remains alert to that threat."
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