A five-year-old boy with autism who went missing and was later discovered unresponsive in a retention pond has died.

Emergency crews were called to the Saddle Ridge area around 5 p.m. Friday for reports of a missing child, and soon after the boy was discovered floating in the nearby body of water.

The boy has been identified as Raheel Uddin. His parents, Rozina Mina and Mohammad Rashad Uddin, say that Raheel had autism, suffered from seizures on a regular basis and was non-verbal.

His mother immediately called 911 after she noticed he was missing, and police and neighbours helped the family search the area.

A passerby on a bicycle noticed the boy’s body in the pond, and entered the water to pull him out.

Emergency Medical Services said the boy was rushed to hospital in life-threatening condition. Police confirmed that he died in hospital shortly afterwards.

Raheel’s mother said she always took extra care with her son.

“He didn’t understand like a regular five-year-old,” Mina told CTV Calgary through tears. “I always treated him as a six-months-old baby.”

She says that Raheel would communicate by touch, or through the noises he could make. He was very close to his family, and Mina says she never went anywhere without him.

It makes the realization that he’s gone that much harder.

"For me, I feel like he is still at school,” Mina said. “I can't say he's passed. To me, he is still alive."

The family is calling for the city to put up fences or barrier around ponds in the city, to prevent another tragedy like this one from occurring.

“We lose our nephew, but we don’t want to lose any more kids,” his uncle Anisul Kabir said.

Police say their investigation is ongoing.

With a report from CTV Calgary’s Stephanie Wiebe