Three more birds have died after being attacked with a pellet gun at TeWinkle Park in Costa Mesa, bringing the total deaths to seven as police continue to investigate in hopes of finding whoever is responsible.

An eighth bird was injured.

Costa Mesa police were initially called to the park April 18 after a mallard, a Peking duck and two Muscovy ducks were found with injuries, Debbie McGuire of the Wetlands and Wildlife Care Center in Huntington Beach said April 21.

Four more birds were found with injuries and taken to the center on April 29, center officials said on Thursday, May 5. They included a mallard, an Egyptian goose and two more Peking ducks.

All but one of the birds, a Peking duck, either died or had to be euthanized due to their injuries, officials said.

The two Muscovy ducks were known to regular park visitors as Mr. Chipper and Grace, and one of the Peking ducks had been named Darryl, McGuire said. They were all killed.

A park regular had told McGuire she had seen them alive  April 17 at 7 p.m.

Costa Mesa police Lt. Ed Everett said investigators believe all the birds were likely shot in a single incident, noting that some of the birds may have still moved around for some time after they suffered their injuries, but police weren’t ruling out the possibility that a second incident occurred.

Investigators believe the shooting occurred overnight while the park was closed, Everett said.

Park rangers have upped patrols of the park and Costa Mesa officers have checked the park periodically after hours since the April 18 call, Everett said. It wasn’t known if the park had surveillance cameras that may have captured the shooting.

“It’s been very stressful and sad for the volunteers, for my staff, for myself and for our wildlife veterinarians,” McGuire said. “It’s not easy when you’re dealing with animal abuse.”

The center was attempting to help police with the investigation by X-raying the birds and extracting ammunition, McGuire said.

The attack has also prompted People for the Ethical Treatment of Animals to offer up a $5,000 reward for information leading to the arrest and conviction of the shooter or shooters.

“There seems to be a serial shooter on the loose, with one bird after another enduring a slow and agonizing death,” Colleen O’Brien, PETA senior vice president, said in a statement.

The suspect would face potential felony animal cruelty charges, Everett said.

McGuire, executive director at the non-profit care facility, said caring for the animals has been expensive because of the X-rays and extended staff time needed.

Some community members who enjoy spending time with the birds reached out to the Wetlands and Wildlife Care Center either directly or through social media comments, McGuire said.

The park sits across the street to the north from the OC Fairgrounds.

Anyone with information was asked to call Costa Mesa Police Detective John Smith at 714-754-5097.