Dallas Cowboys defensive back CJ Spillman is being investigated over an alleged assault, police say.

CJ Spillman, 28, has not been arrested or charged.

The attack allegedly took place at a Texas hotel in the early hours of September 20, according to Grapevine police spokesman, Sgt. Robert Eberling.

The case adds to a recent spate of high-profile incidents involving NFL players.

Earlier this month Baltimore Ravens running back Ray Rice was suspended indefinitely after a video emerged of him punching his then-fiancée.

After Ray Rice was suspended, Minnesota Vikings star running back Adrian Peterson was indicted on child-abuse charges.

CJ Spillman is being investigated over an alleged assault (photo AP)

And Arizona Cardinals running back Jonathan Dwyer has been charged over accusations he broke his wife’s nose during a domestic dispute in July.

The latest incident allegedly took place at the Gaylord Texan Resort and Convention Center, where the Dallas Cowboys stay.

CJ Spillman, a defensive back, played against the St Louis Rams the next day.

Sgt. Robert Eberling said no other details were being released because the investigation was ongoing.

There has been no immediate response from the Cowboys. CJ Spillman’s agent and lawyer declined to comment, the Associated Press said.

On September 30, Cowboys coach Jason Garrett told staff that the club would not allow players accused of domestic violence to play.

Critics have been calling on NFL Commissioner Roger Goodell to step down after Ray Rice initially received just a two-game ban for his assault.

In a public statement earlier this month, Roger Goodell said he “got it wrong” in his handling of the Rice case and pledged to implement new personal conduct policies.

The NFL has announced it is hiring four women as advisers on domestic violence.

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