"A person was detained today in Arlanda and has now been taken into custody… The person was detained on suspicion of a murder attempt and 26 cases of harsh illegal threats," the statement read.
Charges are expected to be brought against the man no later than May 24.
According to local media reports, the man is suspected to have sent written threats to the country's ministers in 2017. Some of the envelopes contained a harmless dust-like substance.
The man is reportedly suspected of a murder attempt undertaken abroad. He went to Thailand at the beginning of 2018 and has only just returned. The Swedish police had been prepared for his return.