A gunman killed at least two people at a United Parcel Service facility in San Francisco, United States, CNN reported on Wednesday. Media reports differed on the number of casualties. The gunman, believed to be an employee at the facility, shot himself, Reuters quoted local media reports.

Security officials are conducting a search for more victims or witnesses. Following reports about the incident, San Francisco police department tweeted saying its personnel were responding to a shooting at a building near the Bayshore Freeway.

Citizens were advised to avoid heading towards the site of the reported shooting while they conduct a search operation.

Liberal gun laws in the United States have been highly debated with the significantly high rate of gun violence.