The visas, known as "green cards," that are to be reviewed apply to citizens from 19 countries that are said to be "of concern," according to USCIS Director Joseph Edlow.
He writes on X that the announcement of reconsiderations comes after orders from President Donald Trump.
When asked by American media about exactly which countries this applies to, USCIS refers to a presidential order from June, in which Trump mentions Afghanistan, Iran, Haiti and Venezuela, among others.
Trump said earlier on Thursday that he wants "every single alien who has entered our country from Afghanistan" to be reviewed and that all immigration cases involving Afghan citizens should be paused.
The suspected perpetrator who shot two US National Guard soldiers on Wednesday is an Afghan citizen and is said to have fought with US forces in Afghanistan and collaborated with the CIA. He lives in Washington state on the US west coast.
He came to the United States in September 2021 and was granted asylum in the country this spring.
The Trump side claims that the man should not have been allowed into the United States and that he was only allowed in because of a decision by former President Joe Biden. However, he was granted asylum when Trump was president.
"The American people should not have to suffer for the previous administration's injudicious relocation policies," writes Joseph Edlow in his post on X.
