An Ohio man is accused of fatally shooting his pregnant sister and brother-in-law at a park on Monday, according to several local reports.

Police alleged that Jason Iverson, 29, shot and killed his sister, Mercedes Iverson, 30, and her husband, Trea Carter, 31, in Maple Heights, Ohio, a suburb of Cleveland,The Plain Dealer,News 5 ClevelandandWOIOreported. A 13-year-old boy was also reportedly injured.

Citing police,The Plain Dealerreported that Mercedes and Carter were at a park for a picnic when Jason showed up. According to police, Jason and Mercedes had been in an ongoing dispute, and when he arrived at the park and saw her, he allegedly tried to fight his family members, the outlet reported.

Subsequently, Mercedes, Carter and the 13-year-old reportedly broke away from the fight and went to their car. At that point, Jason allegedly pulled out a handgun and began shooting at them, News 5 Cleveland reported, citing police. The shots struck Mercedes and grazed the arm of the boy, police said.

Mercedes Iverson/Instagram

Mercedes Iverson and Trea Carter, a married couple, shot and killed along with their unborn child.

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Carter then fled the car, the outlets reported, and attempted to hide, but Jason allegedly chased him and shot in the bathroom, according to police.

Jason was charged with murder and attempted murder and is facing arraignment Wednesday, the outlets reported. It’s unclear if he has retained an attorney or entered a plea. The Maple Heights Police Department did not immediately respond to an inquiry from PEOPLE.

Mother Speaks Out

Cynthia Ivey, the mother of Mercedes and Jason,spoke to WOIOand provided more context on the shooting.

Jason Iverson.Maple Heights Police Dept.

Mercedes Iverson and Trea Carter, a married couple, shot and killed along with their unborn child.

Maple Heights Police Dept.

Mercedes and Carter had been at the park to drop off a stroller as a favor for Ivey, who was attending a church picnic at the park, she told the outlet.

“Then out of the blue you know my son shows up and as soon as he sees them, he just goes off, so I don’t know what he was doing before that got him so enraged, but he just wouldn’t let up,” Ivey told WOIO. “So, we’re like, ‘This is a church function, let’s just leave,’ and so they were leaving, they were in the car when he started shooting.”

Ivey claimed Jason had held a grudge about something and that it “festered,” but she still couldn’t believe that he would have ever tried to kill her, WOIO reported.

Mercedes Iverson and Trea Carter.Mercedes Iverson/Instagram

Mercedes Iverson and Trea Carter, a married couple, shot and killed along with their unborn child.

WOIO reported that Mercedes was a licensed cosmetologist and worked in customer service, while Carter was a postal worker and hosted a podcast.

source: people.com