Kathryn Benson-Billing watched with alarm as a woman holding a toddler leaped onto a picnic table bench Saturday in a concessions area at San Diego’s Petco Park.

The woman lost her balance but jumped back up. Then, within a matter of seconds, she fell. In a horrifying moment, both woman and child tipped over the side of the facility and fell the equivalent of six stories to the street below.

“Everybody was in shock,” said Benson-Billing, who was having a snack in the concessions area when the pair fell. She added: “It just happened so fast.”

The 40-year-old woman and her 2-year-old son were pronounced dead at the scene minutes before the Padres’ game against the Atlanta Braves was to begin Saturday. The San Diego Police Department was still investigating the incident as of Sunday, saying in a news release that the deaths “appeared to be suspicious” and the homicide unit had been called to the scene “out of an abundance of caution.”

Police said the investigation was in its early stages and little is known about the circumstances of the deaths. Authorities have not publicly identified the mother and young son but said they both lived in San Diego.

The boy’s father was at the ballpark, and the woman and child had been at a concession area on the concourse, police Lt. Adam T. Sharki told the San Diego Union-Tribune. Police were eager to speak to people who may have been nearby and could “give the family some peace,” homicide Lt. Andra Brown told the newspaper.

“Our hearts obviously go out to the family, but also to the people who here could potentially be traumatized who saw this,” Brown said. “It’s a horrible, horrible thing. That’s why we’re giving it a very serious look.”

Benson-Billing, who estimated she was about 10 feet from the woman and child when they fell, said she was deeply shaken by what she witnessed.

“I keep reliving it and reliving it,” she said.

She said she “still can’t figure out how exactly it happened,” but noted that the woman had appeared to be happy, jumping around and bouncing her toddler. She spoke with police about what she saw, hoping to help their investigation.

Another man, who asked not to be identified, told the Union-Tribune that his wife saw the two fall and said that the toddler fell from an area with dining tables and the woman fell as she tried to grab the boy.

The Padres said they were keeping their comments limited because the incident remains under investigation.

“We are deeply saddened by the loss of life at Petco Park last evening,” team spokesman Craig Hughner told The Washington Post. “Our thoughts and prayers are with the family of those involved.”

Fans shared their horror over the incident on social media and found it difficult to focus on the game.

“[I don’t care] what happens with this game,” one tweeted. “I am not okay after hearing what happened here today. Hug whoever you can walk or drive to and hug… And for no other reason that they can hug back. Please. Wear your heart on your sleeve and feel braver because of it. Please.”

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