A gunman who opened fire on Wednesday on a college campus in the Dallas suburb of Irving, Texas, apparently killed one victim and committed suicide, police said, two days after a deadly stabbing occurred at another college in the state.

A man who witnesses said was armed with a handgun was reported to have opened fire at North Lake College, prompting authorities to swarm the campus in search of the suspect and victims as school officials imposed a security lockdown.

A short time later, Irving police reported on Twitter that there appeared "to be no continuing threat," adding that law enforcement officers were still searching the campus to ensure all was safe.

A separate Twitter post added: "We have what appears to be one victim deceased (and) the shooter has committed suicide."

The identities of the shooter and the victim were not immediately released, and police spokesman James McLellan said it was too early to tell whether the two people knew each other.

No one else was wounded in the shooting, which occurred at one of the main buildings on campus, McLellan said.

After police said the shooter was dead, college officials announced the school would be closed for the rest of the day.

Overhead video footage of the scene broadcast by local news media showed students filing out of school buildings as police evacuated the campus. Earlier video clips showed students in groups running for safety and numerous police vehicles on campus.

On Monday, a man enrolled at the University of Texas went on a stabbing spree with a large hunting knife at the school's Austin campus about 200 miles (320 km) south of Irving, killing one student and wounding three others, police said.