Authorities in Milwaukee are urgently searching for a missing 4-year-old boy named Nevin Powell, who is believed to be in the company of his 12-year-old sister, Sanuya Wooten-Powell. Concerns are heightened as Sanuya may be armed, according to police reports.

Nevin was last spotted walking along N. Fifth Street in Milwaukee alongside his sister, with the last communication with his guardian occurring on Tuesday night, as reported by WISN.

The young boy is described as having brown hair, standing 3 feet tall, and weighing approximately 50 pounds. At the time he was last seen, Nevin was dressed in a navy blue shirt paired with blue jeans, but was not wearing any shoes.

Sanuya, his sister, is described as being 5 feet 5 inches tall and weighing 130 pounds, with distinctive red hair. Her last known attire included a black jean jacket worn over a black hooded sweatshirt, along with blue jeans.

The siblings may be traveling in a silver or light blue Hyundai Santa Fe that lacks license plates, according to the police. It remains unclear who might be operating the vehicle.

Authorities said they were especially concerned about Nevin because he is not wearing a coat or shoes.

Police say Sanuya is wanted for abduction, WITI said. She also has a warrant for battery to a police officer.

Anyone with information about Nevin, Sanuya, or the vehicle is urged to call Milwaukee police at 414-935-7252.