The search for a man accused of raping a Silver Spring woman and throwing her into the frigid Patuxent River intensified yesterday as Howard County police issued arrest warrants linking him to another abduction in Maryland.

Warrants issued in Howard County allege that Richard Dale Baumgardner, 25, abducted a 29-year-old Columbia woman at knifepoint about 5:30 p.m. Saturday in Columbia.

Howard County police said the woman had been forced into the passenger side of her car, but escaped while the car was stopped at a traffic light. The woman identified Baumgardner from a photograph, police said.

The Howard County warrants charge Baumgardner with kidnaping, armed robbery, assault and theft, police said.

Baumgardner became the focus of a nationwide alert Tuesday after warrants were issued charging him with the rape, kidnaping and attempted murder of a 30-year-old Silver Spring woman. The woman, who had been shopping for groceries, was getting into her car at Wheaton Plaza Shopping Center about 10 p.m. Monday when a man with a knife forced his way into the car, drove her to a Howard County motel and raped her, police said.

They said the man then drove the woman, who had been bound and gagged during the ordeal, back to the Montgomery County line and dropped her 35 feet from the Rocky Gorge Bridge into the Patuxent River.

The woman managed to swim to shore, walk to Rte. 29 and flag down a passing motorist who took her to a pay telephone to summon help, police said.

In the incident involving the woman in Columbia, Baumgardner allegedly "ran up to her with a knife and forced his way into her car," said Sgt. Angus Park of the Howard County police.

"But as he was driving her south on Rte. 29, at about 5:40 p.m., he stopped for a red light at Rte. 29 and South Entrance Road and she jumped out of the car and ran to the car behind," Park said. "The people in that car took her into their car, and the man drove off in her car."

About 11:30 that night, police recovered the woman's car from the parking lot where she had been abducted six hours earlier, Park said.

Montgomery County police said that since the incident Monday they have received hundreds of telephone calls from people who report that they have seen Baumgardner, but he has eluded authorities.

Montgomery County Detective George G. Neville Jr., one of the investigators working on the case, said that Baumgardner apparently has been unemployed and "living out of his truck" since being paroled from the Maryland Correctional Training Center in August 1984.

Baumgardner was sentenced in 1978 to 10 years for rape and 90 days for possession of drugs, according to his parole officer, Maureen Skorko of Ellicott City.

Baumgardner was scheduled to check in yesterday with Skorko as part of the provisions of his parole. Skorko declined to say if she had heard from Baumgardner.

The Silver Spring woman was released yesterday from the Montgomery County hospital where she had been taken for treatment early Tuesday, police said.

The woman, described by police as a single professional, is in good physicial condition but "is having a tremendous emotional reaction" to her ordeal, Neville said.

He said that she is staying temporarily with friends, "but she is fearful . . . and we are doing everything we can to protect her, and her identity."