Students and staff have returned to buildings on the Florida State University campus to retrieve their belongings a day after a gunman opened fire, killing two people and wounding at least six others.

The university issued an active shooter alert at midday near the student union. At least six people have been hospitalized, including one person in critical condition, a spokesperson for Tallahassee Memorial HealthCare said.

At least six people were injured in a mass shooting at Florida State University on Thursday, according to hospital officials, who had earlier confirmed to CNN it was receiving and treating patients from the campus.