US-based extremists radicalized years after entry: Report

US President Donald Trump walks across the South Lawn upon return to the White House on March 2, 2017 in Washington, DC. (AFP photo)

A new report by the US Department of Homeland Security finds that most violent extremists in the US were born in the country or were radicalized "several years after" they entered the US.

The report, obtained by MSNBC on Thursday, found insufficient evidence that citizens of seven Muslim-majority countries included in President Donald Trump's travel ban pose a terror threat to the United States.

The report also said that citizenship of any given country is an "unlikely indicator" of terrorism threats to the US.

"We assess that most foreign-born, US-based violent extremists likely radicalized several years after their entry to the United States ... limiting the ability of screening and vetting officials to prevent their entry because of National Security concerns," read the document.

The new intelligence assessment tracked 88 violent, foreign-born extremists in the United States. More than half of them had been in the US more than 10 years before they were indicted or killed.

The report is seen as a blow to Trump’s stalled executive order to keep potential terrorists out of the country by banning citizens of seven Muslim-majority countries from entering the US.

The order, which was blocked by the federal courts and is expected to be replaced by a new version, put a temporary halt on citizens of Iran, Iraq, Libya, Yemen, Syria, Sudan and Somalia from entering the US, a pause on all refugees and an indefinite ban on Syrian refugees.

The order sparked widespread demonstrations, chaos and outrage, with travelers detained at airports and panicked families searching for relatives.

The Homeland Security report said that of the 82 people the government determined were inspired by a foreign terrorist group to carry out or try to carry out an attack in the US, just over half were born in the United States.

The others were from 26 countries, led by Pakistan, Somalia, Bangladesh, Cuba, Ethiopia, Iraq and Uzbekistan. Of these nations, only Iraq and Somalia were among the seven Muslim-majority countries included in the travel ban.