Wright County Sheriff Sean Deringer said he often gets emotional when he relives Feb. 9, the day when a man entered the Allina Health Clinic in Buffalo and opened fire.

The attack killed 37-year-old medical assistant Lindsay Overbay and seriously injured four others.

But the days since have been full of hope and acts that prove the power of community, he said at a prayer service Sunday night at Buffalo Evangelical Free Church.

Residents have bought meals for the investigators and sent over coffee and doughnuts. The Sheriff's Office has received dozens of thank-you cards and even one birthday card, which was postmarked from California.

In shaky penmanship, its message read: "I wanted you to know that I am praying for you and lifting your staff up in prayer."

On Sunday, participants prayed for victims of the shooting and their families, as well as the law enforcement officers, first responders and the clinic's patients and staff. They also prayed for the suspect, Gregory Ulrich. According to search warrants, Ulrich was angry at the clinic's doctors for cutting off his opioid prescription.

Authorities believe Ulrich's dependence on pain medication was a "driving force" behind his assault on the clinic.

Sunday's service, which drew about 50 people, featured prayers from faith leaders from seven area congregations as well as chaplains, and Buffalo Mayor Teri Lachermeier, Pat Budke, the city's police chief, and Deringer.

Each speaker thanked the community for its outpouring of support and emphasized the need for continued healing for the victims and all Buffalo residents who have been hurt and traumatized by the act of violence.

"I just pray for that peace to return," said Budke. "When I think about how February 9th was almost three weeks in the past, it doesn't seem possible."

As a pianist played the hymn "It is Well with my Soul," several people in the church quietly wiped away tears.

Katie Oxley, the chaplain of Allina Health's Buffalo Hospital, said it has been both a great honor and a great heartbreak to pray with those in the community and guide them through their own grief.

"This is a very vulnerable time and in order to come through it, we need to show up for each other," she said. "And this community has done just that with multiple forms of support."

Residents have illuminated purple lights and worn purple "Buffalo Strong" T-shirts to show solidarity; they've raised money for the victims and their families; and they've held events, like Sunday's prayer service, to create a space for shared grief and healing.

"It's that level of caring for one another that has brought the most traumatized through these last weeks," Oxley said. "It makes me feel like Buffalo can be known for something other than violence. It can be known for its unity and this amazing sense of community."

Jaycie Kratky, the connections director of Buffalo Free Church, has made hundreds of keychains and earrings to sell to raise money for the victims' families and other community outreach efforts.

Each piece features the outline of Minnesota with a small purple heart at its center. So far, she's raised more than $800.

"This community is so important to me and I hate to see it hurting," Kratky said. "I wanted to do whatever I could."

At the end of the service, each person in the church held a small lighted candle. As the lights dimmed, Pastor Greg Braly encouraged those gathered in the church to look around and to take notice of the glowing candles.

"On that tragic day, one person tried to bring darkness into our community," Braly said. "But all these lights can lift us up."