A lockdown at Edinburg CISD's South Middle School was lifted following an investigation into a threatening phone call the campus received, the district said Wednesday morning.

The lockdown was announced shortly before 10 a.m. Wednesday, and news of the lift was received at around 10:32 a.m.

Officers with the district's police department investigated and determined the threat to be "non-credible," the district said.

"Students and staff are safe," a district spokesperson said in a news release.

Additional details were not provided by the district.

This is a developing story, check back for updates.