A massive crowd marched through downtown Dallas on Sunday (local time), protesting President Donald Trump’s immigration policies and demanding the release of students who have been detained by immigration officials across the country, as reported by CNN.

The sea of demonstrators, stretching several blocks, carried American flags as a symbol of unity and patriotism. The march began at a cathedral and ended at City Hall, where protesters gathered in front of a stage to make their voices heard. Many carried signs specifically referencing Mahmoud Khalil, Khan Suri and Rumeysa Ozturk—foreign students  in the US who were arrested.