Since 2012, an estimated 300 people have travelled from Sweden to join Islamist extremist groups in Syria and Iraq, but fewer are now going to those countries, Swedish Television quoted a report from Swedish security service, Sapo.
At the same time, Sapo and leading terrorism experts warn fewer would-be jihadists are travelling to the Middle East could mean there will be an increase in the number of terrorist activities in Sweden and elsewhere.
"Those who can't go down there themselves might decide to carry out attacks here instead," terrorism expert Magnus Ranstorp told Swedish television.
"There is a very serious security situation now, with a growing terrorism threat in Europe. There are several individuals who have gone through terrorist training and who have returned to Europe and are capable of carrying out attacks. IS is also encouraging individuals to carry out attacks," Ranstorp said.
The new figures presented by Sapo on Wednesday show the number of people traveling from Sweden to Iraq and Syria for the first time was at the highest in 2013-2014 and the number of individuals returning after undergoing training or fighting with terrorists has increased since the summer of 2015. However, Sapo did not publish exact figures.
Worsening conditions in conflict zones in the Middle East coupled with increasing difficulty to enter IS-controlled areas are the main reasons why fewer people are going over there, according to Sapo.
"Previously, there were IS-controlled border controls that made it easier to enter the regions," said Sapo press secretary Simon Bynert.
Developments in Syria and Iraq, whether or not IS holds on to its territories and whether the militant group continues to appear successful are all factors that will influence whether or not the number of would-be terrorists' trips will increase or decline, according to Sapo.
At the same time, Sweden's National Center for Terrorist Threat Assessment has presented its latest report which shows terrorism threat is increasing and is now at level three on a five-grade terror-threat scale. According to the center, Sweden is likely to become a target, though other European countries are at greater risk.