Forty Army Ranger students and 4 instructors were hit by lightning during training exercises on Wednesday at Eglin Air Force Base, Fla. The lightning hit at 4:55 p.m. CT when the students were two-thirds of the way through Ranger School's Swamp Phase, according to USA Today.

The students were learning lightning protection protocols at the time of the incident, The Army News reported.

Seventeen students and three instructors stayed overnight at the hospital, and the Army initially stated that nine students and two instructors remained hospitalized Thursday afternoon for observation with non-life-threatening injuries. All had returned to duty by Thursday evening. Keith Boydston, a spokesman at Fort Benning, Ga., stated that the course's two female students were not involved, according to Fox News.

All eyes are on this class, as for the first time, the two women are expected to graduate from the grueling Ranger course. Not all pass, and while some are invited to return and try again in a future course, the two women have finished the most difficult sections of the final phase and are expected to graduate next week.

Colonel David Fivecoat, Airborne and Ranger Training Brigade commander, said that the returning students will have increased medical monitoring as they try to earn their Ranger tab.