Rafael Resendez-Ramirez, the rail-riding fugitive suspected in eight brutal murders, surrendered yesterday to law enforcement officials at a border crossing near El Paso, ending a tense nationwide manhunt that has involved hundreds of investigators in recent weeks.

Under an arrangement brokered by his sister, the 39-year-old Mexican drifter crossed a bridge over the Rio Grande punctually at 9 a.m. MDT and calmly extended his hand to a Texas Ranger who waited for him on the U.S. side, law enforcement officials said. Several family members -- including the sister, who may be eligible for a $125,000 reward -- stood by to witness his arrival, the officials said.

The FBI launched an all-out search for Resendez-Ramirez on June 21, placing him on its "Ten Most Wanted" list after evidence linked him to six slayings committed over six weeks in Illinois and Texas. No obvious motive emerged for these killings or for two prior killings in which he is a suspect. The common factors the slayings share are proximity to railroads -- Resendez-Ramirez's favored means of transportation -- and the merciless treatment of the victims.

Investigators also plan to examine at least 14 other unsolved killings that are similar in some respects to Resendez-Ramirez's alleged crimes, officials said. Police in more than 50 jurisdictions have sought information regarding open cases in which he might be implicated, said Don K. Clark, special agent in charge of the FBI's Houston division, who coordinated the manhunt.

The FBI stoked media attention and public interest in the case in the hopes of having "200 million pairs of eyes" looking for the fugitive, as Clark put it. That effort produced thousands of tips but no confirmed sightings of Resendez-Ramirez. Instead, the break in the case came elsewhere.

"Our strategy was to put as much pressure on this individual as we possibly could," Clark said at a news conference yesterday. That included contact with relatives on both sides of the border. His sister, a U.S. citizen living in Albuquerque, whom law enforcement officials have not identified by name, was first interviewed several weeks ago by investigators searching for clues as to his whereabouts.

Deputy Drew Carter of the Texas Rangers spoke to her several times and won her trust, officials said. Recently, those contacts took another tack.

"When you leave no place to turn, then the alternative is what we asked for last week in a plea, that maybe he ought to turn himself in," Clark said.

On Sunday, the sister called Carter to say that she had been in touch with her brother. In negotiations that continued through Monday, an arrangement was worked out for Resendez-Ramirez to surrender on a single burglary charge related to the 1998 murder of a doctor in a Houston suburb, one of the killings in which he is a suspect.

The FBI's Clark noted that no deal was brokered involving possible charges or punishments, which could include the death penalty. In exchange for his surrender, federal officials agreed only to guarantee his safety and to allow for visits by family members while he is in custody. No decision has been made on whether his sister will receive the reward money, Clark said.

Luis Garcia, the Immigration and Naturalization Service district director in El Paso, said Resendez-Ramirez arrived at the Ysleta border crossing, about 15 miles from downtown El Paso, in a pickup truck with one of his brothers. The vehicle stopped on the bridge just short of the U.S. inspection booths, and the two men got out. Carter of the Rangers and an immigration inspector walked out to meet them and then escorted them both to U.S. soil, where their sister, another brother and a pastor waited along with various immigration and law enforcement officers, Garcia said.

"He looked normal," Garcia said. "He was quiet and unassuming. He answered very openly the questions we asked him in order to be processed."

The slight, bespectacled Mexican gave officers what he said was his real name, Jose Angel Reyes Resendiz, and agreed to be turned over to the Texas Rangers and flown to Houston to face arraignment on the burglary charge.

Resendez-Ramirez gave no clue as to why he decided to give himself up.

"We're all asking ourselves, `Why did he surrender?' . . . I think the pressure got unbearable for him, both in the United States and Mexico," Garcia said.

The fugitive's elusiveness had embarrassed federal authorities, especially after he was apprehended June 2 in New Mexico by the U.S. Border Patrol while crossing into the United States illegally. Even though the INS had been alerted by Texas authorities and the FBI that he was a murder suspect, the agency mistakenly sent him back to Mexico.

The Border Patrol's computerized identification system -- called IDENT -- showed that Resendez-Ramirez was a "recidivist" who had repeatedly reentered the United States after having been formally deported three times and having returned to Mexico voluntarily following apprehensions at least nine times.

But the system failed to list him on its "lookout database" as a fugitive or an alien who had been convicted of a serious crime, even though he had spent at least 11 years in jail for a variety of crimes dating to 1976.

"There was nothing egregious that showed up on the IDENT system on Resendez at that time," Garcia said.

After he was returned to Mexico, Resendez-Ramirez allegedly reentered the United States and killed four more people, U.S. authorities say.

When members of Congress complained bitterly about the release and subsequent killing rampage, INS Commissioner Doris M. Meissner asked the Justice Department's inspector general to investigate the Border Patrol's actions.

In his Mexican home town of Rodeo, Durango, Resendez-Ramirez has a common-law wife, Julieta Dominguez Reyes, and a 3-month-old daughter, Liria. He formerly taught English at a Catholic school there and had worked in the United States as a migrant farm worker since he was 16. He also earned money as a "coyote" guiding illegal immigrants across the border.

Residents of Rodeo have described him as an eccentric loner and devout Pentecostalist who caused no trouble apart from an incident in which he smashed a truck's windshield with a car battery after the driver nearly ran over one of his dogs.

A Suspect's Tracks

Key dates in the case of Rafael Resendez-Ramirez, suspected in eight slayings in Texas, Kentucky and Illinois:

Aug. 29, 1997: Christopher Maier, 21, is killed as he and his girlfriend walk along railroad tracks near Lexington, Ky.

Dec. 17, 1998: Claudia Benton is found sexually assaulted, stabbed and beaten to death inside her Houston-area home near railroad tracks. Her vehicle is later found in San Antonio, with one of Resendez-Ramirez's fingerprints inside.

May 2: Minister Norman Sirnic, 46, and his wife, Karen Sirnic, 47, are found dead inside their home near tracks in Weimar, Tex. Their stolen pickup is found in San Antonio.

June 2: Resendez-Ramirez is picked up by Border Patrol agents for illegal entry and sent back to Mexico. Agents said they didn't know he was wanted by police and the FBI.

June 4: Josephine Konvicka, 73, is found slain inside her Fayette County, Tex., home.

June 5: Noemi Dominguez, 26, is found beaten to death at her Houston-area home.

June 15: The bodies of George Morber, 79, and his daughter, Carolyn Frederick, 51, are discovered at their home in Gorham, Ill. The house is 100 yards from a railroad track.

Yesterday: Resendez-Ramirez surrenders near El Paso.

CAPTION: The suspect in a series of killings is escorted into an El Paso courtroom.

CAPTION: Law enforcement officials in El Paso escort suspected serial killer Rafael Resendez-Ramirez toward an airplane that was to take him to Houston.