BERLIN (AP/WGN) — Police in southern Germany are appealing for photos and videos taken by witnesses of an attack near Neuschwanstein castle in which an American man allegedly pushed two University of Illinois alums down a steep slope, killing one of them.

A suspect was arrested following the attack.

German news agency dpa quoted police as saying Friday that they have so far received about a dozen submissions on a specially created website, but assume many more images were taken by tourists present at the site.

“We are looking for photographs which, by chance, show two young women and a man (approx. 30 years old) who were staying east of the Marienbruecke,” Kempten police said on their website. “These persons may have been walking together or separately.”

The Marienbruecke, or Mary’s Bridge, is a popular vantage point for photos of Neuschwanstein, the most famous of the castles built by King Ludwig II of Bavaria in the 19th century.

According to the initial police investigation, the suspect met the two female tourists, Americans aged 21 and 22, on a hiking path and lured them onto a trail that leads to a viewpoint.

“The younger of the two women was attacked by the suspect,” police spokesman Holger Stabik said. “The older one tried to rush to her aid, was then choked by the suspect and subsequently pushed down a slope.”

The assailant then appears to have attempted to sexually assault the 21-year-old before pushing her down the slope as well, prosecutors said. She fell nearly 50 meters (165 feet), ending up close to her friend.

Both women were recovered by mountain rescuers. Eva Y. Liu, 21, was flown to a hospital with serious injuries and later died. Kelsey Chang, 22, remains hospitalized, but is “responsive,” police said.

Neighbors of Liu are at a loss of words after the 21-year-old Naperville native was killed in the attack.

“My heart breaks for them. I’m just – very upset,” neighbor Debbie Krull said. “It’s hard to comprehend it. I mean, you can, but you don’t want to I guess, is the thing I’m trying to say.”

The suspect, who was not identified, remains in custody on suspicion of murder and attempted murder, prosecutors said, adding it wasn’t clear how long he had been in the country.

The U.S. Embassy in Berlin said it was aware of the incident and the consulate in Munich was in contact with authorities.

“Due to privacy considerations, we are unable to comment further at this time,” the embassy said in a statement.

Robin Kaler, an associate chancellor for the University of Illinois Urbana Champaign, said both women graduated last month.

Chang received a Bachelor of Science in Computer Engineering and Liu received a Bachelor of Science in Computer Science.

“Our University of Illinois family is mourning the senseless death of Ms. Liu and the attack on Ms. Chang,” Kaler said in the statement. “Both had just graduated in May and should have been able to celebrate such an important accomplishment without the fear of such a tragic outcome. Our thoughts are with Ms. Chang as she recovers and with both of their families as they grieve.”

Both Chang and Liu graduated from the Illinois Mathematics and Science Academy in Aurora.

The Illinois Mathematics and Science Academy released the following statement:

“Eva was a dedicated, academically talented and involved student. She served as a student leader in her Residence Hall coordinating programming for her peers and fostering a safe and supportive environment. She was a member of the Student Planning Committee for the 2018 International Student Science Fair held on the IMSA campus assisting with programming for 250 students from 32 different countries.  Eva was an adept student researcher who participated in IMSA’s Student Inquiry and Research program studying the effects of high levels of CO2 on the proliferation of skeletal muscle stem cells. Here is a link to her research project.

On behalf of our administration, faculty and staff, we are saddened by this loss and we grieve for and with her family and loved ones. The loss of any student, particularly in such a tragic way, deeply hurts us all.”