The Hartford Police and three of the city’s trauma centers will join new sponsors Saturday, May 18, in what they hope will be largest gun buyback in Hartford to date.

The collaborative effort, called the Capital Region Gun Buyback Program, will offer gun owners $150 for assault weapons, $75 for handguns and revolvers, and $25 for shotguns and rifles in the form of Stop & Shop gift cards.

The Stop & Shop Supermarket Company, the Connecticut Trial Lawyers Association, CT Transit, Lamar Advertising Co. and Hope Street Ministries are among the new partners of the project. This year will also be the first time that Hartford State’s Attorney Gail Hardy will work with the coalition and will allow buybacks to happen anonymously.

According to Hartford Police Department Communications Director Nancy Mulroy, at previous buybacks, gun owners were required to provide personal information before the trade was accepted. The hope is that anonymity will attract more people.

“We want to make this as safe and comfortable for individuals to get rid of firearms as possible,” Mulroy said.

Lamar Advertising has also donated digital billboard space throughout the region to advertise the event, and financial contributions — including $10,000 from the Trial Lawyers Association — has allowed the group to offer larger gift cards.

Trauma surgeons Brendan T. Campbell and David S. Shapiro, and Hartford Police Chief James Rovella, who spearheaded the original gun buyback initiative four years ago, said the initiative is meant to address an ongoing problem and not just respond to a tragedy.

“This is more than just a reaction to the shootings at Sandy Hook, which has brought renewed interest in understanding and preventing gun injuries in death,” they said in a joint statement. “Gun violence has been a problem in American cities for decades and is now getting the benefit of increased attention.”

Mulroy added that the group is not seeking to take a position on gun control. “This is about gun safety,” she said.

An educational table will also be set up at the event to offer information and demonstrations about gun safety. Additionally, locks that can be used to fasten gun lock boxes will be given out for free.

The buyback program is meant to augment existing gun violence prevention programs such as the Hartford Shooting Task Force, which was established in 2011 to diminish gun violence in the capital city. In its first year of operation, the task force boasted a 31.4 percent reduction in shooting victims and 29.4 percent reduction in first-degree assaults with firearms.

Saturday’s event will be hosted from 9 a.m. to 3 p.m. at the Community Renewal Team’s office at 555 Windsor St. in Hartford. The coalition has planned two more buybacks for August and December.