The boy was camping with family in an area with spotty cell service, which resulted in a delayed 911 call, the sheriff’s office said.

BOULDER COUNTY, Colo — A 4-year-old boy has died after he was pulled from St. Vrain Creek about 1.5 miles away from where he went into the water and was swept away Tuesday evening, according to the Boulder County Sheriff’s Office.

At around 5:30 p.m., the sheriff’s office received a 911 call for a water rescue in South St. Vrain Creek near Lyons, said Vinnie Montez, public information officer for BCSO. The boy and his family were camping in the area. Due to limited cell service in the area, they flagged down a passing driver who gave them a ride to an area with reception.

It was initially reported that two children had been swept away, but one of them was rescued quickly.

“There was another child that was in the river, but they were able to get out with no problem,” Montez said.

Rescuers from multiple agencies assisted with the search to find the child, and crews started to search the area from where the campsite was located to the east end of Lyons, the sheriff’s office said.

About 90 minutes after the 911 call, first responders found the boy in the water. The child was taken to the hospital in critical condition. In an update Tuesday morning, the sheriff’s office said he died.

The sheriff’s office reminded people who are recreating outdoors this summer to be prepared and have a plan in case of an emergency and limited cell service and communications.

“Whether you’re in Boulder County or any other county, pay attention. Have an emergency notification method so you can get the information that you need,” Montez said. “You just want to stay tuned to what’s going on in that area wherever you’re recreating.”

The Boulder County Coroner’s Office will determine the cause and manner of the boy’s death.