An attacker severely beat two Miami-Dade County high school students with a tree branch early Monday, family members said.

Bela Perdomo, 15, and James Critz, 16, who are students at the Marine Academy of Science and Technology at Florida International University Biscayne Bay Campus, were collecting samples for a science project near the school when the man approached them.

"About three to five minutes later, he was on top of them bashing the guy with a large club," Elizabeth Perdomo, Bela's mother, told Local 10 News.

Bela and James are both being treated at Memorial Regional Hospital in Hollywood. Family members said both teens are heavily sedated after suffering skull fractures.

Bela told her mother that man did not take anything from them.

"The motive was probably sexually oriented," Perdomo said.

According to an FIU news release, the victims identified the attacker to police as a black male between the ages of 16 to 18.

Miami-Dade County Public School Superintendent Alberto Carvalho said FIU police will be providing extra security on campus after the attack. He also said a crisis team will be on hand when students return to school Tuesday.

The time and place of the attack has unnerved the parents.

"It's not like they were hanging out in some secluded, you know, bad area, so that's what's scary for me," James' mother, Tara James, said.

Bela was Local 10's Eco Hero winner in 2017. Her work creating a non-toxic, chemical-free alternative paint to prevent barnacle growth is what boosted her past hundreds of applicants.

Police said they are looking at surveillance video and following up on any tips that come in.

"This incident is very unusual -- how it occurred, where it occurred. It's a safe campus. Clearly, we're increasing the patrols now as a consequence," FIU President Mark Rosenberg said.

Anyone with information about the attack is asked to contact FIU police at 305-348-2626 or Miami-Dade Crime Stoppers at 305-471-TIPS.

"I'm not going to stop until we catch this fool," Perdomo said.

Students and staff at the Biscayne Bay campus are urged to be extra vigilant and walk in groups or with a friend.

University officials said parking services aides are available at the campus to accompany students and staff members to their vehicles. To request an aide, call 305-348-3615.

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