Twenty of the suspects were women, said Sven-Åke Petters, a spokesperson with the Dalarna police.

“It is too early to say why that is, but it feels as if it is very unusual,” he said.

The situation with such a large number of female suspects in a child pornography case is unique, according to detective inspector Björn Sellström at Sweden’s National Investigation Department (Rikskriminalen).

“This is extremely unusual. Many here are flummoxed by this and it will be very interesting to follow the case and understand the reasons,” he said to TT.

According to Sellström there have been only a handful of convictions against women for child pornography crimes.

Police conducted the coordinated raids at 12 locations across the country, acting on information garnered from an ongoing investigation in Dalarna in central Sweden.

A 42-year-old man remains in custody in connection with the Dalarna investigation and an inspection of his films and pictures led police to the slew of other people and locations, according to a Dalarna police statement.

Two women in Kronoberg, aged 47 and 54-years-old, were among those arrested, with a police statement confirming that there are links to the 42-year-old man.

A further 55-year-old woman was arrested in Halmstad on suspicion of the same offence, reported Sveriges Radio (SR) Halland.

Four women were arrested in Västra Götaland – reported by SR to be in the municipalities of Ale, Mellerud, Tidaholm and Trollhättan.

The 23 suspects all had prior warrants issued for their arrest and so all of those detained in Wednesday’s raids have been formerly arrested.

There remain outstanding arrest warrants for a further two suspects, one of which is reported to be in hospital, while the other has not been located.

The suspects will now be interrogated, and a number of computers and mobile telephones seized in the raid will also be examined.

“This examination and the interviews which are to be held with the suspects will then form the basis for any motions to remand,” Petters said.