The severe beating of a U.S. Park Police officer Sunday night occurred after he approached two brothers and a woman who were drinking beer in Rock Creek Park, court documents revealed yesterday.

One of the men, Hector A. Salamanca, 35, was arrested Monday and charged with assault on a federal officer while armed. Members of a special Park Police tactical unit spent part of yesterday searching for his brother, Jose B. Salamanca, 38.

Police investigating the severe beating -- described yesterday as highly unusual for the Park Police force -- tracked the two suspects through identification found at the scene, according to the criminal complaint filed in U.S. District Court yesterday.

The wounded officer, James P. Culver, 24, apparently asked the two men for some form of identification, said the complaint, which also added that officers later found a D.C. driver's license for Jose Salamanca and an identification card for Hector Salamanca.

The documents, as well as Culver's badge, key ring and flashlight, were in a grassy area near the scene of the beating, which occurred in Grove 13 in Rock Creek Park.

Culver was still listed in critical condition yesterday at Washington Hospital Center, where he was suffering from multiple fractures and bruises to the brain.

His brother, John Culver, said last night that the officer has been able to recognize and communicate with family members and medical personnel, as well as to follow objects with one eye. Small splinters of shattered facial bone will have to be removed soon from his brother's other eye, John Culver said.

James Culver's fractured jaw cannot be wired in place until the swelling subsides in his face and head, his brother said.

In another case, the body of an unidentified woman was found yesterday on the 2000 block of Park Road NW, near Rock Creek Park, police said.

There were no apparent injuries to the victim, who was found by police about 1:40 a.m. The Medical Examiner's Office will determine the cause of death after an analysis that could take several days, a police spokeswoman said.

Details of the assault on the officer emerged yesterday in court documents relating to the arrest of Hector Salamanca, who has been charged with assaulting a federal officer while armed.

Salamanca was held without bond after a brief hearing in U.S. District Court yesterday. A preliminary hearing is set for Thursday.

Authorities have not released a motive for the beating, but the police report on the incident indicates that the two Salamanca brothers and the woman were drinking when Culver approached. The woman was questioned yesterday but not detained, police said.

Culver, who had begun his shift just 1 1/2 hours earlier, apparently decided to check on the three. Police said yesterday that he could have cited the three for parking after the park closed and for possession of an open beverage container, a violation that could lead to an arrest.

In a statement to investigators, Hector Salamanca said he and his brother were drinking beer when the officer arrived, the court document said. He initially told investigators that Jose Salamanca and the officer argued, but then changed his mind and said he did not understand what was going on because he does not speak English.

Hector Salamanca said he left the park while his brother and the officer were talking and drove to his apartment in the 1400 block of Tuckerman Street NW. While there, he told investigators, Jose Salamanca called and said "he had a problem with the police but would not elaborate."

The two brothers live on the same block. Hector Salamanca was arrested Monday afternoon after locking himself in his apartment for more than an hour. When he was captured, the complaint said, he told investigators: "It's not me you should be worried about, it's my brother."

Jose Salamanca was driving a bronze-colored, four-door Isuzu Trooper. Park Police are asking anyone with information to call 619-7105 or 433-1050.