According to a press release from the Swedish Security Service, the suspicion is about "planning of a possible attack in Somalia".
"It is a person arrested today on suspicion of conspiracy to commit terrorist crimes, and he is since earlier charged in his absence, on probable grounds suspected for this,” says deputy chief prosecutor Agnetha Hilding Qvarnström, at the International Public Prosecution Office in Stockholm, to news agency TT.
The suspect was born in 1984 and have Somali origin, according to newspaper Expressen. He was seized by heavily armed police squad.
Hilding Qvarnström confirms that the matter has links to the case in Gothenburg, where another person is detained as a suspect. That case has been linked to the Somali terrorist organization al-Shabaab.
The Security Service says that several more persons will be heard in the ongoing investigation.