Watch CBSN Live

Cops believe missing Neb. boy "was thrown" into river

OMAHA, Neb. -- Crews are searching a Nebraska river for a missing boy after making an arrest in the murder of his mother, reports CBS affiliate KMTV.

Police say they have reason to believe five-year-old Josue Ramirez-Marinero "was thrown" into the Elkorn River at the Highway 275 Bridge in Omaha, according to the station.

A massive search was launched for Josue after his 11-month-old brother, Angel Ramirez-Marinero, was found abandoned in an Omaha dumpster Wednesday evening, "in fair condition"and clad only in a diaper. The body of the boys' mother, Jesus I. Marinero, 45, was discovered in a ravine several miles away shortly afterward, reported KMTV.

The three had been reported missing from their La Vista home that morning.

According to the Omaha Police Department, 25-year-old Roberto Martinez-Marinero went to Douglas County Dept. of Corrections Thursday evening and told authorities there that he was involved in the death of Jesus I. Marinero, his mother. Police say he has been booked for first-degree murder and use of a deadly weapon to commit a felony, reports the station.

Crews were continuing to search the river for Josue, who was the subject of an Amber Alert Thursday after authorities said he was abducted. The alert was canceled after a 2000 silver Jeep Cherokee Laredo, in which investigators said Josue had been traveling, was found abandoned.

The vehicle had two empty car seats inside, but there was no sign of the child.

After Roberto Martinez-Marinero's arrest, the Omaha Police Department announced on its Facebook page that there are "no other suspects being sought."

The Omaha Police Department is conducting a multi-agency ground, water, and air search of the Elkorn River near the Highway 275 Bridge.

Police say Josue has short black hair and was last seen wearing a gray shirt and gray sweatpants.

Anyone with information is asked to contact the Homicide Unit at (402) 444-5656 or Crime Stoppers at (402) 444-STOP (7867).