AUSTIN (KXAN) — More than 20,000 students in the Austin Independent School District were absent on Thursday, hailed as “A Day Without Immigrants” by advocates wanting to show what they called the critical importance of immigrants in the American economy.

Exactly 20,008 students were absent in the school district Thursday, compared to only 4,216 the previous day. AISD says they have 83,591 students in 130 schools — that’s almost 24 percent of their students marked as absent.

A large number of restaurants and businesses in Austin shut their doors, and student walkouts and marches have become a common sight in the past week. Organizers encouraged immigrants and their supporters to not go to work, as well as refraining from buying or selling anything Thursday.

Pflugerville ISD say they experienced a higher than normal number of absences Thursday. While they are still gathering their attendance data, only a handful of schools had attendance below 70 percent.

Friday, students in Manor walked out of classes and caused traffic delays while protesting on US 290. The district said around 50 students at Manor High School were part of the protest; no one was arrested.

Protests against immigration enforcement have been seen nationwide since an ICE operation targeted undocumented immigrants with convictions or arrest warrants in several states.

In Austin, 51 were arrested as part of Operation Cross Check. The Department of Homeland Security estimated that around 75 percent of those arrested nationwide had previously been convicted of crimes.