Same-Sex Teen Couple Shot: Friends and family plan vigil for Mollie Olgin and Mary Chapa

(CBS) PORTLAND, Texas - Friends and family of two teenage girls in a same-sex relationship will hold a candlelight vigil Friday, one week after the shooting incident that left one girl dead and the other severely injured.

Pictures: Same-sex teen couple shot in South Texas park

Mollie Olgin, 19, was pronounced dead at Violet Andrews Park and her apparent girlfriend, 18-year-old Mary Chapa, was hospitalized with a gunshot wound to the head. Chapa is in stable condition, although she has not been formally interviewed about what happened.

Portland Police Chief Randy Wright said both girls were found in a knee-deep grass area by a couple Saturday morning, MSNBC reported. Police are investigating the shooting and haven't established a motive yet.

Rainbow ribbons, goodbye messages and flowers were posted around the scene of the crime.

"It's something that I think all of us are going to carry with us for a while," Frank Reyna, a friend of both girls, told MSNBC. "It's going to take a while to get past this, the idea that there is somebody still out there that did this to these two amazing, beautiful people, and that they're walking free right now."

Wright said police recovered a bullet casing from a large-caliber gun at the scene, which suggests the shootings could have occurred around the same area where the couple was found. They haven't found the weapon.

Wright told MSNBC he believes the shooting was "not just a random attack," but police need more time before they develop anything substantial.

"I cannot imagine anyone who would want to hurt such a loving and caring person," Olgin's friend Chandler Nunez told MSNBC. "This was incredibly unexpected and the lack of answers makes this tragedy all the more frustrating."

Friends said the couple had been together since mid-February and their relationship "was a readily-accepted thing."

"We focused on their personalities and how they got along with everybody else," Reyna told MSNBC. "We didn't care ... what they were, it's who they were."

While people in the south Texas community prepare for the Friday vigil, another candlelight vigil for the  couple has been organized for Wednesday evening in San Francisco by Cleve Jones, a gay civil rights activist who conceived the AIDS Memorial Quilt.

More on Crimesider
June 26, 2012 - Teen female couple shot in South Texas park, one dead, police say