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STOCKHOLM, Nov 20 (Reuters) - Sweden's interior minister said on Friday a police raid in which a young man was detained on suspicion of preparing a "terrorist crime" could be followed by more arrests with the Nordic country on its highest ever security alert.
The raid, which resulted in the arrest on Thursday of a suspect in a building complex in northern Sweden housing asylum seekers, unnerved the country as it came only days after the Islamist militant attacks in Paris that killed 129 people.
Citing unidentified sources, Swedish news agency TT said the raid was carried out after foreign security services passed on information to Sweden about suspicious encrypted communications between the country and the Middle East.
"I do not rule out more arrests," Interior Minister Anders Ygeman told reporters in Brussels.
Prosecutors on Friday submitted documents to a district court showing the apprehended man, identified as Moder Mothama Magid, 22, was suspected of having plotted in Stockholm to carry out an unspecified "terrorist crime". Unconfirmed Swedish media reports said Magid was an Iraqi national.
A lawyer for Magid had no comment on the case and had not yet been in contact with his client. Magid has been arrested on "good grounds" of planning an attack, the second lowest of four levels of criminal suspicion in the Sweden legal system.
The warning of a high probability of an attack jarred Sweden, prompting many commuters in Stockholm to avoid mass transit trains and triggering a security clampdown at potential targets as well as a government push to increase surveillance.
Authorities would not comment on Swedish media reports that up to 10 accomplices could be involved.
"We will have to see if we get interesting information that means more people should be arrested or questioned," said Dan Eliasson, Sweden's national police chief. "This will gradually become clear today and tomorrow."
A resident in the area of the raid described how scores of police with helmets and masks had descended on a neighborhood called the Red Square by locals. Sweden's Migration Agency rents apartments in the complex for use by asylum seekers.
Several people were being questioned by police after the raid.
The security alert was made public on Wednesday but residents in the Boliden neighbourhood interviewed by local media said Magid had been living there for several weeks.
"He is from Iraq and lives here with one person from Syria, two from Iraq and two from Eritrea," the daily Expressen quoted a neighbour, who declined to be identified, as saying. (Reporting by Sven Nordenstam, Johan Sennero, Daniel Dickson Johan Ahlander and Simon Johnson; Writing by Niklas Pollard; Editing by Alistair Scrutton)
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