The superintendent of a Texas elementary school where an 18-year-old gunman shot and killed 18 children and three adults said his heart is broken today.

Hal Harrell, superintendent of the Uvalde Consolidated Independent School District, said Tuesday that Robb Elementary School will be closed and all school activities will be cancelled until further notice. Harrell also said grief counselors would be available starting Wednesday morning.

“My heart is broken today,” Harrell said. “We’re a small community and we’re going to need your prayers to get through this.”

The death toll increased Tuesday evening. State Sen. Roland Gutierrez said he’d been briefed by state police on the latest fatalities from the school in Uvalde, a heavily Latino community about 85 miles west of San Antonio.

In addition to 21 dead, three people injured in the shooting remain in serious condition, Gutierrez told The Associated Press. The gunman is dead, likely killed by police.