SAN ANTONIO (CBSDFW.COM/AP) – An FBI supervisor in Texas says he’s concerned additional attacks could occur after shots were fired at a building housing federal immigration enforcement personnel.

FBI Special Agent in Charge Christopher Combs said during a news conference, “We cannot allow political discourse to lead us to the point of violence.”

Combs says at least one vehicle pulled up to a building in San Antonio early Tuesday that houses offices for U.S. Immigration and Customs Enforcement and a gunman fired shots through a window.

San Antonio ICE Office shooting (CBS)

He says the building has several tenants and the gunman must have known where the ICE offices were located.

No one was injured, but that one office was occupied at the time of the shooting.

Combs says another San Antonio building used by ICE also was fired on Tuesday.

(© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)