Reports of gunfire at Houston-area transportation company

Officers respond to reports of a deadly shooting at the Knight Transportation office in Katy, Texas, Wednesday, May 4, 2016. Authorities said a recently fired employee opened fire at the transportation company. (KPRC Houston via AP) MANDATORY CREDIT (The Associated Press)

In this frame from video, officers respond to reports of a deadly shooting at the Knight Transportation office in Katy, Texas, Wednesday, May 4, 2016. Authorities said a recently fired employee opened fire at the transportation company. (KPRC Houston via AP) MANDATORY CREDIT (The Associated Press)

Officers are responding to reports of gunfire at a transportation company near Houston.

The Harris County Sheriff's Office says deputies responded Wednesday following reports of a shooting at a Knight Transportation office in Katy, about 20 miles west of Houston. The office didn't immediately return phone messages for details.

Numerous patrol vehicles are surrounding the facility. A nearby high school is on lockdown as a precaution.

A message left with Phoenix-based Knight Transportation also wasn't immediately returned. The company provides truckload transportation services.