SOUTH CAROLINA – Many injured passengers in South Carolina were brought to a hospital on two buses after a train collision early Sunday morning.

Palmetto Health emergency room doctor Eric Brown said the hospital quickly changed a tent they were using as a waiting room to keep people away from patients with the flu into a triage area to diagnosis the injured Sunday.

"We were really well coordinated, very ready, we had the opportunity to create capacity not only in our main acute emergency room area but also to set up a triage in our tent which we ironically set up several days ago to be prepared for the flu surge, which we were able to repurpose this morning as our triage setting. And, in doing so, having coordination, communication, and preparation - it went very, very well," he said.

Authorities say 116 people were taken to four hospitals. Brown says four were admitted to the three hospitals run by Palmetto Health with one in critical condition and two in serious condition. The rest were treated and released.

The passengers were on an Amtrak train that slammed into a freight train that authorities say was parked on a side track near Cayce around 2:45 a.m. Sunday.

Officials say the passenger train's conductor and engineer were killed.