(MAQUOKETA CAVES STATE PARK, Iowa) — The assailant in the deadly attack on a family vacationing at an Iowa state park last month shot, stabbed and strangled the victims, according to newly released autopsy results.

Tyler Schmidt and Sarah Schmidt, both 42, and their daughter, Lula Schmidt, 6, were found dead at their Maquoketa Caves State Park campsite on the morning of July 22, authorities said.

The Iowa Department of Public Safety released the results of their autopsies on Thursday. The Iowa Office of the State Medical Examiner determined that Tyler Schmidt died from a gunshot wound and multiple sharp force injuries, Sarah Schmidt died from multiple sharp force injuries, and Lula died from a gunshot wound and strangulation, authorities said.

All three deaths have been ruled homicides.

A suspect in the attack, 23-year-old Anthony Sherwin, of La Vista, Nebraska, was also found in the park dead from an apparent self-inflicted gunshot wound, authorities said at the time.

An autopsy determined Sherwin died of a self-inflicted gunshot wound, and his death has been ruled a suicide, the Iowa Department of Public Safety said.

Sherwin is still considered the lone suspect amid the ongoing investigation, authorities said Thursday. The Iowa Department of Public Safety said in a statement that “the known facts and circumstances, and all evidence collected to this point, substantiate Sherwin was the perpetrator of the homicides and acted alone.”

Authorities have not commented on whether or not the suspect knew the victims. No further updates in the case, including a possible motive, were provided.

The Schmidts, who were from Cedar Falls, leave behind their 9-year-old son, Arlo, who survived the attack, according to Cedar Falls Mayor Rob Green.

Sarah Schmidt was an employee at the Cedar Falls Public Library, Green said.

On Tuesday, the Cedar Falls community held a celebration of life for the three Schmidts killed in what Green called a “devastating” loss.

“We hold this celebration to memorialize how much Sarah, Tyler and Lula meant to us as friends, neighbors, co-workers and classmates,” Green said during the celebration.

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