USA TODAY Sports

Pittsburgh Steelers assistant coach Joey Porter allegedly assaulted a doorman and was arrested on multiple charges on Sunday night, Pittsburgh police said in a news release.

Porter, 39, faces aggravated assault, simple assault, resisting arrest, public drunkenness, and terroristic threats charges after an off-duty officer, who was serving as a security guard at a South Side restaurant, witnessed Porter assault the employee of the nearby bar.

"Once he arrived on the scene, the officer stopped the assault and arrested (Porter)" Pittsburgh police said in a statement early Monday morning.

Porter was transported to the Allegheny County Jail.

Chris Mueller of The Beaver County Times first reported the arrest in a series of tweets Sunday night.

The Steelers released the following statement late Sunday night:

“We are aware of an incident tonight involving Joey Porter. We are still gathering information as it pertains to the situation, and we will have no further comments until we get more details.”

A former 13-year NFL veteran who spent eight seasons with Pittsburgh, Porter now coaches the Steelers linebackers.

The Steelers defeated the Miami Dolphins on Sunday in an AFC wild-card playoff game and are scheduled to play the Kansas City Chiefs next Sunday.

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