(CNN) -- A child on a school outing was attacked by a leopard at a Wichita, Kansas, zoo, authorities said Friday.

The boy, a student from Linwood Elementary, was with classmates on a field trip at the Sedgwick County Zoo when, around 1:15 p.m., witnesses said, he "went over a railing" and approached the Amur leopard exhibit, said Lt. Jay McLaurian of the county sheriff's department.

The leopard was able to reach into the mesh covering of its enclosure and grab the boy by his head, McLaurian said.

The child was rescued by bystanders who rushed in and "beat the animal" away from the boy, officials said. According to McLaurian, the boy received injuries to his face and neck and was taken to a hospital for treatment.

He is expected to "be OK," McLaurian said.

The boy, who is 7 years old, was in fair condition Friday afternoon at Via Christi Hospital on St. Francis in Wichita, CNN affiliate KWCH said.

Students from several Sedgwick County schools were at the zoo on Friday and witnessed the attack, and the school district immediately took steps to notify parents, according to Susan Arensman, spokeswoman for Wichita Schools.

"One of our first-graders was injured by one of the animals," a letter that was sent home to parents whose children attended the same school as the victim read.

A similar letter was also sent home to parents from other Wichita schools.

Shortly after the attack, school officials assembled a crisis team to help the students process what happened, and assure them that the victim would be OK, said Arensman.

"Counselors will also be available on Monday to offer additional help to students," Arensman said.

The zoo was evacuated for a short time after the attack but remained opened after the incident, officials said.

Amur leopards, which are listed as an endangered species, can grow to 4 to 6½ feet long and weigh anywhere from 60 to 150 pounds, the zoo's website says. They are native to Far Eastern Russia and northern China.