Nine Britons were among 13 suspects held in a series of dawn raids by armed officers in a massive operation backed by Britain's Serious Organised Crime Agency.

Among the drugs seized were 3,600 ecstasy pills from the same batch believed to have killed British holidaymaker Jodie Nieman, 20, on the Spanish island in July.

Arrests: Nine Britons were among 13 suspected drug dealers (pictured here) held in a series of dawn raids by armed officers in Ibiza

Officers also confiscated 4 kilos of cocaine, 5 kilos of MDMA powder, 53 grams of cannabis resin, 300 doses of anabolic steroids, 69,000 euros (£60,000) in cash and scales for weighing drugs.

The operation, codenamed Rula, was run by the Civil Guard's Organised Crime Squad.

The force released photographs of some of suspects, handcuffed behind their backs, following the raids.

The Civil Guard said in a statement: 'The majority of the pills seized are known as Pink Rock Stars, similar in appearance, colour and design to those thought to have caused the death of a young British woman and the poisoning of eight other people in July in Ibiza.'

The suspects appeared before an investigating magistrate and most were remanded in custody while the probe continues. They have not yet been charged with any offence.

The Civil Guard statement continued: 'This operation has completely dismantled the most active group of British drug dealers in Ibiza.

Suspected: Among the drugs seized (right) were ecstasy pills from the same batch believed to have killed Jodie Nieman in July 

'Those under arrest are members of the most active organisation on the island, the principal supplier of cocaine and other designer drugs around nightclubs.

'The investigation started with information obtained through the dismantling of other groups, mostly British, dedicated to dealing drugs on the island.

'The now dismantled group came to Ibiza during the summer to cater for the high demand for drugs that exists during the holiday period.'

On July 22 police arrested an alleged member of the gang carrying one kg of MDMA powder as he stepped off a flight from the UK at Ibiza airport.

Five of the raids took place on August 28 around the popular party resort of San Antonio. 

Evidence: Police arrested nine Brits - from Liverpool, Manchester, Plymouth and Croydon, south London - as well as three Irishmen and one Polish man

The other three happened on the same day near Sant Josep, on the south west of the island.

Police arrested nine Brits - from Liverpool, Manchester, Plymouth and Croydon, south London - as well as three Irishmen and one Polish man.

Magistrate Maria Risueno took statements from the suspects at the Court of Investigation number 1 in Ibiza.

She bailed one man and remanded the other 12 in custody on Monday night.

Three were told they would be released if they could raise 10,000 euros (£8,700) each for bail.

The magistrate imposed a secrecy order on the case and the court refused to reveal the names of those arrested.

Nail technician Jodie Nieman, from Croydon, collapsed at Space nightclub while on holiday with friends on July 13.

She died after being rushed to the island's Can Misses hospital. Her friends told police she had taken one pink ecstasy tablet mixed with alcohol.

Toxicology tests are still being carried out. Eight other clubbers were treated in the same hospital that night.

Counting out: 69,000 euros in cash was found during the raids