OTTUMWA, Iowa (AP) -- Authorities have resumed their search for a 16-year-old boy who ran into the Des Moines River in Ottumwa to rescue his dog.

Rescue crews from the Wapello County sheriff's office and Ottumwa Fire Department put boats into the river Wednesday evening to search for the boy, who authorities identified as Marco Arroyo. Crews also searched along the levees and from bridges but were unable to find him.

The Ottumwa Courier is reporting that Arroyo ran into the river about 8 p.m. Wednesday but was pulled under by the current and did not resurface. His dog was able to swim back to shore.

The search was called off Wednesday night because of darkness. The search resumed Thursday morning.