A federal immigration agent died and another was injured in a shootout that followed a confrontation between the U.S. Immigration and Customs (ICE) officers in Long Beach, California, the latest reports said.

An unspecified dispute broke out between ICE agents Thursday evening in the Glenn M. Anderson Federal Building near the city's oceanfront, the Los Angeles Times reported, citing law enforcement sources.

The LA Times reported that the nature of the dispute had not been established, but that the shooter had opened fire on his supervisor while another officer tried to overpower the gunman.

The situation began ... as an incidence of workplace violence involving two federal agents in their office space. When the incident escalated, one agent fired several rounds at the other agent, wounding him, CNN quoted Steven Martinez, assistant director of the FBI office in Los Angeles, as saying.

No further details of the incident, which happened on the seventh floor of the building, were available. Law enforcement officers are investigating the unfolding case.

The CNN report has said the names of the victims have been withheld until their families are informed about the incident.