HOUSTON, Jan. 22 (Xinhua) -- All schools in a Texas city were placed on lockdown Wednesday after a man made a threat against at least one campus, local media reported said.

Authorities in Columbus, a city about 128 km west of Houston, received the phone threat on Wednesday morning, the website of the Houston Chronicle reported.

Officials did not release details about the threat or the suspect. However, they said it was mainly directed toward a high school.

Police said officials with the Columbus Independent School District locked down all schools as a precaution. No injuries were reported and the lockdown was lifted about an hour later, according to the report. All activities have returned to normal, police added.

It's not immediately known if any arrests have been made for the phone threat. Authorities have not revealed other details.