STOCKHOLM (Reuters) - Swedish security police said on Thursday they had arrested a person suspected of plotting a terrorist crime as well as illegal weapons possession in a case with connections abroad.

The SAPO security police said they made raids in western Sweden following extensive information-gathering. Several people were being interviewed in addition to the person arrested.

“The person has carried out preparations for the suspected terror crime for some time and there are international connections,” SAPO said, without giving an identity.

Police spokesman Gabriel Wernstedt declined to say which countries the case was linked to, but said the operation had no known links to a gun attack on a Christmas market in Strasbourg on Tuesday. French police are still hunting a man suspected of killing at least two people.

Sweden, where an Uzbek asylum seeker mowed down pedestrians with a truck and killed five people in Stockholm last year, has kept its terrorist threat level unchanged at elevated, which is a three on a scale of five.