Oklahoma Gov. Kevin Stitt is commending one of the state's school districts for suspending more than 100 students who participated in a walkout protesting U.S. Immigration and Customs Enforcement last week.

Officials at the Mustang, Oklahoma, public school district confirmed that a number of students received in-school suspensions for truancy after several students took part in the protest, reports ABC affiliate KOCO 5.

The district did not say how many students were affected, but Stitt, in a social media post, said that he applauded "Mustang Superintendent Dr. Charles Bradley for suspending 122 students who walked out of class to protest."

Stitt, a Republican, continued, "Young Oklahomans: Free speech is sacred, but truancy robs your future. Stay in school, build skills, and make your voice heard responsibly."

Mustang Public Schools students joined peers from other districts across Oklahoma in walkout protests during school hours, leading state leaders to discuss the impact of the demonstrations and their legality.

The school district said that it notified parents about the planned student-led walkout and said that the district did not sponsor or approve of it.

Students were expected to attend class, the district told parents, asking them to "reinforce those expectations at home."

Students who walked out were given in-school suspensions for their unexcused absences, which resulted in missed instruction time, but they were not disciplined for their speech or viewpoint, the district said.

"Consequences were applied for leaving class and missing instruction during the school day," school officials said.

Lawmakers last week condemned the walkouts and called for investigations to determine if staff members were involved. Their letter initially listed Mustang but left out the names of districts in a revised version, reports outlet KOSU-NPR.

"Mustang Public Schools is aware of recent statements issued by Oklahoma lawmakers regarding student walkouts that have occurred across the state," the district responded in a statement.

"We are grateful to [state] Senator Paul Rosino, State Superintendent Lindel Fields, and Oklahoma Secretary of Education Dan Hamlin for reaching out to learn the facts surrounding the student walkout at Mustang High School and allowing us, as the local school district, to respond to this situation based on verified information and established policy," the statement added.

The district also said it did not find evidence of staff involvement.

"Despite social media claims alleging adult involvement, district leadership reviewed all allegations and found no evidence that any Mustang Public Schools employee instigated, organized, or facilitated this student activity," the statement said.

"Individuals identified in online posts as district employees were either not affiliated with Mustang Public Schools or were inaccurately represented."

Meanwhile, Texas Attorney General Ken Paxton on Monday announced his office is investigating three other school districts over student walkouts, with the probes to target North East Independent School District, Dallas Independent School District, and Manor Independent School District, following a similar inquiry into Austin Independent School District.

Paxton, a Republican challenging incumbent Sen. John Cornyn, R-Texas, for his seat, said his office is probing whether school officials had failed to prevent classroom discussions and maintain safety and whether employees helped organize the demonstrations.

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