Three students were treated and released from Virginia Hospital Center late Thursday after they and members of their tour group showed symptoms of dehydration.
A large tour group of students and their chaperones from Texas spent the day in Washington, D.C., and Thursday night began feeling sick, Arlington County Fire Department Capt. Gregg Karl said.
About half of the group was already back at their hotel at 1500 Arlington Blvd. when they began to feel ill. The others were on a train heading into Rosslyn Station.
Arlington County police and fire, along with Metro transit police were called to the station shortly after 9 p.m. Thursday.
One of the teens vomited on the Metro platform, prompting other students to "stampede" out of the station, Metro spokesman Dan Stessel told Patch.
Emergency responders arrived and began treating the students.
For 13 minutes riders were unable to enter the Metro station, though all passengers could exit. Rail service continued to operate normally and the "all clear" was given at the entrance at 9:25 p.m., Stessel said.
The children who were hospitalized have been released back to their chaperones, Karl said.
The group is going about getting fluids back in their bodies.
"If people are going to be coming to visit here, on these hot days, remember to wear light-colored clothes, drink adequate fluids the day before, and get fluids in you throughout the day," Karl said. "Don't wait until you're thirsty, because then you're already dehydrated."