Far-right extremists have ramped up an intimidating wave of anti-Semitic harassment against Jewish journalists, political candidates and others ahead of next month's U.S. midterm elections, according to a report released Friday by a Jewish civil rights group.The Anti-Defamation League's report says its researchers analyzed more than 7.5 million Twitter messages from Aug. 31 to Sept. 17 and found nearly 30 percent of the accounts repeatedly tweeting derogatory terms about Jews appeared to be automated "bots."But accounts controlled by real-life humans often mount the most "worrisome and harmful" anti-Semitic attacks, sometimes orchestrated by leaders of neo-Nazi or white nationalist groups, the researchers said."Both anonymity and automation have been used in online propaganda offensives against the Jewish community during the 2018 midterms," they wrote.Billionaire philanthropist George Soros was a leading subject of harassing tweets. Soros, a Hungarian-born Jew demonized by right-wing conspiracy theorists, is one of the prominent Democrats who had pipe bombs sent to them this week. The ADL's study concludes online disinformation and abuse is disproportionately targeting Jews in the U.S. "during this crucial political moment.""Prior to the election of President Donald Trump, anti-Semitic harassment and attacks were rare and unexpected, even for Jewish Americans who were prominently situated in the public eye. Following his election, anti-Semitism has become normalized and harassment is a daily occurrence," the report says.The New York City-based ADL has commissioned other studies of online hate, including a report in May that estimated about 3 million Twitter users posted or re-posted at least 4.2 million anti-Semitic tweets in English over a 12-month period ending Jan. 28. An earlier report from the group said anti-Semitic incidents in the U.S. in the previous year had reached the highest tally it has counted in more than two decades.For the latest report, researchers interviewed five Jewish people, including two recent political candidates, who had faced "human-based attacks" against them on social media this year. Their experiences demonstrated that anti-Semitic harassment "has a chilling effect on Jewish Americans' involvement in the public sphere," their report says."While each interview subject spoke of not wanting to let threats of the trolls affect their online activity, political campaigns, academic research or news reporting, they all admitted the threats of violence and deluges of anti-Semitism had become part of their internal equations," researchers wrote.The most popular term used in tweets containing #TrumpTrain was "Soros." The study also found a "surprising" abundance of tweets referencing "QAnon," a right-wing conspiracy theory that started on an online message board and has been spread by Trump supporters."There are strong anti-Semitic undertones, as followers decry George Soros and the Rothschild family as puppeteers," researchers wrote.