Suspect Malik Faisal Akram was killed during a rescue operation to save a rabbi and three worshippers who were held at gunpoint at the Congregation Beth Israel for nearly 12 hours on Saturday.
Akram, a British national, reportedly demanded the release of Aafia Siddiqui, a Pakistani neuroscientist who was convicted in the US in 2010 and sentenced to 86 years in prison for trying to kill an American army captain in Afghanistan.
At a news conference after the hostages were released, FBI Special Agent in Charge Matt DeSarno said “the Texas synagogue hostage taker’s demands were specifically focused on issues not connected to the Jewish community”.
Kenneth Marcus, a former assistant US secretary of eduction for civil rights, said the attack on the synagogue in Colleyville, near Fort Worth, was “obviously a matter of antisemitism”.
“The FBI got it wrong,” Mr Marcus, who is also the founder and chairman of the Louis D. Brandeis Center for Human Rights Under Law, told Fox News.
Roz Rothstein, CEO of StandWithUs, a non-partisan organisation that educates people about antisemitism, said the FBI comments “dangerously downplayed” what was an obvious attack on Jewish people.
“Trying to separate Jews from the idea that Jews were targeted on their holy day at their house of worship, is a mistake and it is insulting and disappointing,” Ms Rothstein told Fox News.
“It makes no sense to try and separate Saturday’s hostage crisis from the people who suffered and who were the most impacted: Jews, their Jewish families and the Jewish world,” she added.
Ms Rothstein said the FBI agent may have misspoke because antisemitic acts are often allowed to pass without being properly identified or condemned, either “intentionally or out of ignorance”.
Their comments echoed an outpouring of anger from US politicians and commentators over the remarks.
Late on Sunday, the FBI clarified its initial statement by stating that the siege was a “terrorism-related matter, in which the Jewish community was targeted”.
“We never lose sight of the threat extremists pose to the Jewish community and to other religious, racial, and ethnic groups. We have had a close and enduring relationship with the Jewish community for many years,” the statement said.
“We continue to work tirelessly with the Secure Community Network, the Anti-Defamation League, the Jewish Federation, and others to protect members of the Jewish community from all potential threats.”