(VOVworld) – Chris Harper Mercer, 26 years old, has been identified as the gunman who opened fire at Umpqua Community College in Roseburg, Oregon, on Thursday. No personal information about the gunman has been released.

Authorities check bags as students and staff are moved off campus at Umpqua Community College after shooting report. (Photo: ‏@MikeSullPhoto)

Investigators questioned Mercer’s family and friends and searched for his recent activities on social networks to clarify the motive for his crime.

Mercer was not a student at Umpqua Community College.

Witnesses said that about 40 shots were fired Thursday morning. The shooter was himself shot down by police. At least 15 people were killed and 20 others injured.

President Barack Obama condemned the violence and called for stricter controls on guns and ammunition which have been postponed by Republicans since 2013.