A Swedish government study says there's been a recent surge in the number of automated Twitter accounts ahead of the Sept. 9 election, noting that 40 percent of them are more likely to support the anti-immigration Sweden Democrats party, expected to make gains.

The study by Sweden's defense research agency comes amid broader concerns over misinformation ahead of the election. 

Researcher Johan Fernquist said the number of so-called Twitter bots discussing politics nearly doubled from July to August.

The report published Wednesday said users "may be led to believe that this content (is) more widely accepted or more mainstream than it actually is."

The FOI agency noted that "it is 40 percent more common that the bots express support for the Swedish Democrats compared to what genuine accounts do."

FOI, which analyzed almost 600,000 tweets from more than 45,000 accounts, did not say who might be behind the bots.

"Hopefully, this study will contribute to a greater awareness of possible effects of the bots, so more citizens make their decisions without being affected by them," Fernquist said.

Swedish authorities repeatedly have talked about the potential risk of foreign inference in the vote.

Last year, Sweden's domestic intelligence agency briefed lawmakers about the potential risk of foreign inference in the vote to renew the 349-seat Riksdagen.

At the time, Prime Minister Stefan Lofven told Swedish broadcaster SVT that it has "become increasingly obvious that foreign powers are trying to influence an election and its outcome." He added, "obviously Russia was active in the U.S. elections" and "we cannot assume that we are immune."

Polls suggest that the Sweden Democrats—currently the country's third largest political group but considered a pariah in Swedish politics—could become Sweden's second largest party and surpass the main opposition party, the liberal Moderates. Sweden's largest party, the ruling Social Democrats, built the country's famed welfare state.

The Sweden Democrats, born out of a radical nationalist movement with neo-Nazi links, has softened its rhetoric and expelled openly racist members. It gained popularity amid the debate about immigration, a key topic in the election.

The Scandinavian country of 10 million took in 163,000 refugees during the dramatic influx of migrants in Europe in 2015—the highest per-capita rate in Europe. At 375