In 1994, Howard County held a gun buyback event at which residents turned in 15 firearms. At a similar event in 1995, county residents handed in three guns.

But at a buyback held over the weekend in the suburban Maryland county, the first there in 18 years, the number of guns exchanged for cash soared to 631.

“Clearly there was an interest and a need in our community for an event like this,” said Police Chief William McMahon.

Events at which firearms are turned over to authorities, often in exchange for cash or gifts, have been held for years, in the Washington area and throughout the United States.

However, news accounts suggest that they have been held in greater numbers since recent mass shootings in Newtown, Conn., and elsewhere raised concerns about firearms kept in households.

A news report from North Andover, Mass., said that a family there had offered up to $2,600 in gift cards to encourage the handover of guns that people no longer wished to keep.

The North Andover police chief was quoted as saying that the family “wanted to do something in memory of those victims” — those who were killed in Newtown — and wished at the same time to prevent future gun violence.

In the Howard County buyback, authorities received 314 handguns, 168 rifles and 149 shotguns.

They also took in some ammunition and some BB guns.

The turnout “shows that many people have firearms in their homes that they don’t want or need,” Howard County Executive Ken Ulman (D) said in a statement.

“There are now hundreds of fewer rifles and handguns in Howard County that could fall into the hands of children or thieves and cause real damage,” he said.

The $100 given for each firearm came from asset forfeiture funds seized in drug investigations, the Howard police said.

The number of firearms turned in at the Saturday event appeared to compare favorably with other jurisdictions where such events have occurred. For example, the rate of buybacks in Howard was about three times as great, per resident, as at a December event in Los Angeles.