Updated 9:36 PM ET
HOUSTON A fight between two people erupted in gunfire Tuesday at a Houston-area community college, catching a maintenance man in the crossfire and leaving students and others cowering in classrooms.
No one was killed, but the volley of gunshots heard shortly after 12 p.m. on the Lone Star College campus sparked fear of another campus massacre just more than a month after 26 people were killed at an elementary school in Newtown, Conn.
The school's official Twitter feed said earlier the shooting was between two people and that the situation was under control. It had issued an alert on its website, telling students and faculty to take immediate shelter or avoid the campus.
"I saw two dudes basically get into an altercation and the dude that shot, he basically got angry and started shooting the other guy," student Brittany Mobley told CBS affiliate KHOU Houston. "A lot of people heard a lot of shots."
The shooting happened outside between an academic building and the library where Luis Resendiz, 22, was studying on the second floor. An employee called police and then herded the 30 to 40 people in the library into a small room and told them to crouch down, he said.
Keisha Cohn, 27, was in a building about 50 feet away and began running as soon as she heard the shots.
"To stay where I was wasn't an option," said Cohn, who fled to a building that houses computers and study areas. All the students eventually were evacuated, running out of buildings as police officers led them to safety.
Authorities offered no details about what led to the fight. One of the people involved had a student ID, and both people were wounded and hospitalized, Harris County Sheriff's Maj. Armando Tello said. A fourth person also was taken to a hospital for a medical condition, he said.
Mark Zaragosa said he had just come out of an EMT class when he saw two people who were injured and stopped to help them.
"The two people that I took care of had just minor injuries," he told KHOU-TV. "One gentleman had a gunshot to the knee and the (other) actually had an entry wound to the lower buttocks area."
The shooting last month at Sandy Hook Elementary School heightened security concerns at campuses across the country. Resendiz said the Connecticut shooting was the first thing he thought of when he heard gunfire and he wondered if a similar situation was happening on his campus.
"I didn't think something like this could happen. You don't think about it happening to you," he said.
Several school districts in Texas have either implemented or are considering a plan to allow faculty to carry guns on campus. While guns are not allowed on college campuses, the Texas Legislature this year may debate a bill that would allow them.
Richard Carpenter, chancellor of the Lone Star College System, said the campus is a gun-free zone that "has been safe for 40 years."
"We think it's still safe," he added. He also described the maintenance man, who was said to be in his 50s and listed in stable condition, as "in good shape."
Police evacuated and closed the campus after the shooting. It reopened in the late afternoon, with classes expected to resume Wednesday.
The noise that rang through the second-floor tutoring lab where Daniel Flores was studying initially sounded to him "like someone was kicking a door."
"I didn't think they were shots," said Flores, 19.
About 60 people were in the lab, and they began running out of the room once they realized the sound was gunfire, he said. They fled to a nearby student services center, where authorities kept them there for about 30 minutes before letting them go.
Cody Harris, 20, said he was in a classroom with about six or seven other students waiting for a psychology class to start when he heard eight shots. He and other students looked at each other, said "I guess we should get out of here," and fled.
"I was just worried about getting out," Harris said. "I called my grandmother and asked her to pick me up."