Unaware that they had been videotaped, Los Angeles police officers and supervisors downplayed the level of violence used to arrest Rodney G. King by claiming that he suffered only cuts and bruises "of a minor nature," according to internal police documents reviewed by The Times.

In contrast, three California Highway Patrol officers who watched how the police officers attacked King were so "shocked" at the brutality that they took note of the officers' name tags.

"I didn't see any need to hit him with a baton," CHP Officer Melanie Singer later told investigators.

These conflicting accounts of the March 3 incident in Lake View Terrace are contained in hundreds of pages of confidential police reports, witness interviews and other official materials collected by investigators and studied by the Los Angeles County grand jury, which indicted a sergeant and three officers last week.

The documents lend substantial new detail to the early morning arrest that prompted allegations that the beating fits a pattern of abuse by Los Angeles police officers and has spurred calls for the resignation of Chief Daryl F. Gates.

Central to the case against the officers is an amateur videotape of the beating that has been telecast nationwide. Contrary to what police officers initially reported about King's arrest, the 25-year-old parolee from Altadena was struck up to 56 times. His doctor says he suffered a dozen broken bones.

The Times, which gained access to the grand jury records, found:

* Sgt. Stacey Koon, the lead Police Department supervisor at the scene, reported that although the officers repeatedly struck King, the man's injuries appeared to be light.

In his daily report, filed before his shift ended that day, he wrote: "Several facial cuts due to contact with asphalt. Of a minor nature. A split inner lip. Suspect oblivious to pain."

Koon also stated that the officers "delivered a torrent of power strokes, jabs, etc., to arms, torso and legs. . . . Taser (a police stun gun) going the entire time. Finally wore suspect down."

* In Use of Force reports submitted by Koon and Officers Laurence M. Powell and Timothy Wind, they listed King's injuries as only "contusions and abrasions."

They also marked boxes on the Use of Force reports stating that King "attacked officers," "continued some resistance" and "increased (his) resistance."

In fact, the videotape shows that King is often in a defenseless position as the officers circled and hit him repeatedly.