A days-long search for a missing baby boy in Louisiana has ended after a truck driver spotted the one-year-old crawling through the grass alongside a busy highway.

Sheriff Gary Guillory told the BBC that the child's discovery "was a miracle", after he survived alone outdoors for "two days with no water and no food".

Calcasieu police had been searching for the baby since 8 July, the day they found his four-year-old brother deceased in a nearby pond.

The same day, a press release sent out by police caused a local media storm that led to the arrest of Aaliyah Jack, the boys' mother, in Mississippi, hundreds of miles away.

Ms Jack is in jail in Meridian, Mississippi, awaiting extradition to Louisiana on a charge of failing to report a missing child.

Mr Guillory said that additional charges may be added.

The baby was taken to hospital and released on Wednesday to child protective services.

"We call him a miracle baby," Sheriff Guillory said.

"He did have insect bites all over his body, but he was in good spirits. We're just thankful."

The sheriff said the weather worked in their favour.

"The sun never really came out and heated up the air," he said, referring to Louisiana's often brutal summer temperatures.

"We had some remnants from [Hurricane] Beryl, some extra cloud coverage that probably kept his body cool. We were very lucky."

The sequence of events leading to the baby's rescue began on Monday when the Calcasieu Parish Sherrifs Office received a call about a body being located in a pond near the Vinton Welcome Center.

"Our first priority was to get it out to the news media and get some leads," Mr Guillory said.

"And that's exactly what happened."

On Monday evening, the sheriff's office received a call from a grandmother who had seen the reports and was concerned about her grandchildren.

She told police the four-year-old had a younger brother, which caused police to issue a 'bolo' (be on the lookout) alert for the missing one-year-old and his mother.

Ms Jackson was arrested at a train station in Mississippi hours later.

On Tuesday morning, a marine division of the sheriff's office was boating through the pond where the brother had been found, searching for the missing boy.

They then received a call around 09:00 EST (14:00 BST) from a truck driver along Interstate-10 near the Texas-Louisiana border who said he had seen a baby "crawling" through a nearby ditch.

Mr Guillory said the investigation is ongoing and the cause of death for the four-year-old is currently unknown. An autopsy report is pending. (BBC)