Serious crime in the District of Columbia continued to soar last year, increasing 13 percent over 1979 and reaching the highest level since 1971, according to a year-end D.C. Police report.

Robberies jumped 28 percent and burglaries 21 percent, all figures underscoring earlier reports of big monthly and quarterly increases throughout 1980.

The total for serious reported crimes -- murders, rapes, robberies, aggravated assaults, burglaries, larcenies and auto thefts -- came to 63,668 in 1980, 13 percent higher than the 54,430 in 1979 and the largest number since 1971 when 70,516 serious offenses were reported.

The upsurge has sent District residents scurrying to area security firms for protective devices such as burglar alarm systems, iron bars for windows and doors, tear gas and other chemical sprays. The rise also has sparked the proliferation of residential block clubs with neighbors watching out for each other's property.

"Lately people have been desperate," said Frank Burgess, owner of Ace Iron Works, which installs bars on windows and doors. "We are getting calls every day from people who have been broken into."

"We have had an enormous rise [in business]," said John Bonney, president of Atlantic Security and Protection, Inc. "We have had to put on additional staff. . . . It used to be that people would call and want alarm systems installed as a preventive service. Now they want it because they have actually been burglarized."

Ed Dempsey, a sales manager for Wells Fargo Service, said that after accused master burglar Bernard C. Welch was arrested in December after Washington physician Michael Halberstam was slain, Wells Fargo received telephone calls from eight people on the same street where Halberstam lived.

According to the D.C. Police yearend figures, homicides increased 11 percent from 180 in 1979 to 200 in 1980. Reported robberies jumped from 6,920 to 8,897. Burglaries leaped from 13,452 to 16,260.

Larcenies rose from 28,819 in 1979 to 31,068 in 1980, an 8 percent increase, according to the figures, and aggravated assaults were up 9 percent from 2,964 to 3,236.

Only rapes and auto thefts showed declines. Rapes dropped 9 percent from 402 to 365, and auto thefts dropped 1 perent from 3,606 to 3,568.

Police officials yesterday blamed the increase on inflation, unemployment and the increased availability of heroin and other illicit drugs in the city.

"It's a multitude of things," said Asst. Chief Maurice Turner. "No one thing . . . . Times are tough."

Area security firm owners said residents appear to becoming more aware of crime in their neighborhoods.

Jim Walker, vice president of Beltway Alarm Services, Inc., said his company has received numerous calls from people who tell them that their neighbor's home has been burglarized. "They want to do something now before it happens to them."

Ronnie Brown at Armour Iron Works said more customers are requesting iron bars on windows and doors. "They want something that will be deterrent," he said. "Alarm systems alert you after someone has broken or tripped a wire. People are going for something stationary. Something that will keep them out."

Dealers in chemical sprays say they also are doing a booming business.

"We sell tear gas like it's going out of style and a lot I'm sure is going to the District of Columbia," said Larry Denny, owner of the Cop Shop in Arlington.

Ronnie Poling, manager of Crawford International, Inc., which sells law enforcement and military equipment, said he receives a lot of calls for both handguns and tear gas, "but we can't sell the guns" in the District, which has one of the strictist firearms control laws in the country.

While scurrying for security devices, residents also have begun to form block clubs to look out for each other's property.

On Oakwood Street SE, where recently three elderly residents were killed and numerous homes were burglarized, residents have formed a block club. "We are our neighbors' keepers," said one resident, who said neighbors are joining together to watch out for strangers. Some neighbors have volunteered to install stronger locks and peep holes in several homes on the street.

In one Capitol Hill block club, several men have volunteered to walk female neighbors from a Metro subway stop to their homes in the late evening.