Acting ICE Director Todd Lyons verified the shooting during a conversation on CNN on Wednesday.

“It could be employees, it could be civilians that were visiting the facility, it could be detainees,” Lyons said of those who were shot.

“At this point, we’re still working through that.”

Two individuals were transported to a medical facility with gunshot injuries, and another person was pronounced dead at the site following the shooting, as stated by Dallas police spokesperson Officer Jonathan E Maner in an email.

Parkland Hospital has accepted two patients from the incident at the ICE facility, hospital representative April Foran mentioned over the phone. She did not have specific information about their conditions.

Authorities were called to assist an officer on North Stemmons Freeway at approximately 6:40 am on Wednesday (9:41 pm AEST) and initial findings suggested that an individual discharged a firearm at a government edifice from a nearby structure, Maner indicated. The investigation is underway with a briefing scheduled later in the day.

Homeland Security Secretary Kristi Noem noted that details were still unfolding, but the agency confirmed there were “multiple injuries and fatalities” at the field office.

Noem said the motive remained unclear, but noted there has been an uptick in targeting of ICE agents.

Dozens of emergency vehicles were seen along a highway near the facility.

The ICE facility is situated along Interstate 35 East, just southwest of Dallas Love Field, a major commercial airport serving the Dallas-Fort Worth metro area, and a short distance from hotels accommodating airport visitors.

Traffic cameras near the scene showed six lanes of a normally busy freeway empty, with cars and semitrailers ground to a halt on an interstate exit.

ICE and Homeland Security didn’t immediately provide additional details.

The Dallas Fire-Rescue Department was dispatched at 6.41am after a call reporting a shooting at or near the immigration office, department spokesperson Jason L Evans said in an email.

Evans said he didn’t have any confirmed details he could share, calling it an active and ongoing incident.

A July 4 attack at a Texas immigration detention centre injured a police officer, who was shot in the neck.

Attackers dressed in black military-style clothing opened fire outside the Prairieland Detention Centre in Alvarado, south-west of Dallas, federal prosecutors said. At least 11 people have been charged in connection with the attack.

A man with an assault rifle fired dozens of rounds at federal agents as they were leaving a US Border Patrol facility in McAllen on July 7.

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