LOS ANGELES » Two young women found dead in a popular Los Angeles park appear to have died of significant head trauma, police said.

Autopsies were still pending on the women and will confirm what killed them, but both had wounds to their heads significant enough that they were hard to recognize, Lt. John Jenal, a spokesman for the Los Angeles Police Department, said Friday.

The autopsies were expected to be done by the end of next week.

A woman walking her dog found the bodies Wednesday in Ernest E. Debs Regional Park, 20 miles northeast of downtown Los Angeles. Both were fully clothed, showed no signs of sexual assault, and are thought to have been in the park for under a week, investigators said.

One of the women was identified as 19-year-old Gabriela Calzada. Police said the other was 17 but haven’t confirmed her name. The two appear to have been friends.

No arrests have been made or suspects identified.

Police have added officers on foot inside the park and in patrol cars in the area following the discovery of the bodies. The officers were assigned to the park to ensure safety and to ask people in the area if they’ve seen anything suspicious or heard any screams in the park recently.

“We’re on high alert. We’re worried,” police Capt. Patricia Sandoval said. “It’s very alarming, especially for anybody that’s a runner, a hiker or a walker who uses that park regularly and thinks, ‘Am I in harm’s way now?'”

Police haven’t received any recent complaints of anything unusual in the park, Sandoval said.

Last year, police asked for the public’s help to identify a man in connection with attacks on three women at the park in a six-month period. One of the women reported being groped as she walked alone, another reported that a man exposed himself, while a third said a man armed with a knife punched her and stood over her for several seconds before fleeing.

Residents in the area expressed deep concern over this week’s discovery.

Rosalia Lopez, who said she visits the park nearly every day, told The Los Angeles Times that she and other women have discussed how unsafe they feel now.

“It takes away the tranquility of the place,” she said. “You have to be more alert now.”