Updated May 3: Revised to include additional information about a person of interest.

Police are asking for help in identifying a person of interest after a Fort Worth teenager was bloodied fending off a possible abduction attempt as she was walking to a school bus last month. The attacker is still at large, police said.

Fort Worth police shared video and photo of a man detectives hope to ask about anything he may have witnessed. He was not being named a suspect, police spokesman Chris Britt said.

"I’ve been told this is just a person they’d like to speak to, just based on that they don't know who he is right now," Britt said. "They want to speak to everyone."

The person of interest is described as a white male between 5-foot-8 and 5-10 and about 200 pounds. He has dark, medium-length hair and a thin beard and mustache. In the video, the man is wearing jeans, a gray shirt, a dark baseball cap turned backward and a black pullover sweatshirt.

1 / 3 2 / 3Police released a photo of a person of interest in reference to the assault of a 13-year-old girl in Fort Worth on Thursday. (Fort Worth Police Department) 3 / 3

He swings a dark-colored backpack over his shoulders in the video, which police said was taken near the time and location of the attack. Police noted there were distinct patterns on the side of the backpack.

Britt said the department is encouraging anyone who may have witnessed or captured video of the attack to share information with police. He said police were not interested in any criminal history of potential witnesses.

The attack happened just before 7 a.m. April 19 near Calmont Avenue and Laredo Drive in West Fort Worth. A bus driver called 911 to report that a 13-year-old student had gotten on the bus and was bleeding and unresponsive.

Authorities said a man approached the girl, who attends International Newcomer Academy, as she walked to the bus.

"He attacked her," district spokesman Clint Bond told the Fort Worth Star-Telegram. "But she fought him off."

Police are treating the attack as an assault, but are leaving open the possibility that it was an attempted abduction, police Capt. Deven Pitt said.

"We don't know what the motive was," he said.

The attacker, who appeared to be a stranger, fled and remains at large, police said. Sgt. Chris Britt described the assailant as a white or Hispanic man who is 30 to 40 years old and was wearing a light shirt and dark pants.

Authorities said the girl had cuts and bruises and was taken to Cook Children's Medical Center for treatment.

Police said the girl remained in serious condition Tuesday, and her injuries prevented her from talking with investigators.

Anyone with information is asked to call police at 817-392-4430 or Crime Stoppers at 817-469-8477.