Some 200 possibly violent Islamic extremists live in Sweden, according to an intelligence report released Wednesday after the country's first-ever suicide bombing narrowly missed Christmas shoppers.

"The group of active members ... consists of just under 200 individuals," the Säpo intelligence agency said in its 126-page report, based on data from 2009 and scheduled to be published before the weekend's attack in central Stockholm.

Saturday's bomber, named as Taymour Abdelwahab, a Swedish national who became an outspoken supporter of violent jihad while living in Britain, did not figure among the 200 people on Säpo's radar, and it remained unclear if any possible accomplices were on the list.

"We are currently putting enormous resources into assessing his contacts, his whereabouts, his profile, and to see how his radicalisation process began and how it developed," Malena Rembe, the chief analyst at Säpo's counter-terrorism unit, told AFP.

"I can say we are studying very, very carefully to ... be able to assess the risk or the threat," she said, adding it still remained to be seen if the bomber had helpers.

The report showed that the number of violence-promoting Islamists in Sweden has remained stable in recent years.

While the so-called radicalisation process generally happens among men aged 15 to 30, the average age in the group is 36, the report showed.

Rembe explained that while members of other violent, radical groups, like rightwing extremists, tended to drop out when they started families, the radical Islamists "don't leave when they get older," making prevention work at an early age vital.

The report showed "most of them were born or grew up in Sweden, and it is here that they come into contact with violence-promoting ideologies and groups."

Some "80 percent of the 200 can be linked to each other," Rembe told a press conference, adding however that the connection tended to be loose, through friendship and acquaintances, and not as part of one big network.

Around 30 out of the 200 have in recent years traveled abroad to take part in violent combat or terrorist training camps, she said.

"Most of these networks focus on action and propaganda against foreign troops in Muslim countries and against governments they see as corrupt and not representing what networks consider to be the only true interpretation of Islam," Saepo said.

It explained in the report that the extremists focus on areas such as Somalia, Iraq, Afghanistan and Pakistan.

But while most of Sweden's radical Islamists did not yet consider the Scandinavian country a legitimate target, Rembe pointed out that a recent rise of the far-right and increased anti-Muslim rhetoric could alter that.

"What we've seen in other countries where you have a more polarised debate, where you have more open xenophobia or Islamophobia, is that it tends to push people into movements because they feel isolated in their own society and they feel included in these extremist environments ...

"So it is a potential negative outcome," she told AFP.

She added however that Sweden today has "a fairly open dialogue and communication ... It is extremely important to ensure a nuanced discussion."

Abdelwahab, known for his outspoken views in favour of violent jihad, blew himself up on Saturday evening minutes after his car exploded, injuring two people, near a crowded pedestrian street in Stockholm.

He killed himself before he could carry out what, according to the lead prosecutor on the case, appeared to have been a mission to murder "as many people as possible."