Twin sisters aged three both drown in Texas apartment complex pool months after their brother died of an illness

Twin three-year-old sisters have drowned in a Texas apartment complex - just months after their brother died, according to several sources.

Police responded to the pool at the Ridgeview Apartments in Sherman, about 65 miles north of Dallas, on Wednesday following a 911 call.

The sisters, Elena Lalnun and Glory Ram, were found unconscious, underwater, by a maintenance worker who pulled them out, as reported by CBS News. 

It's unclear who was watching the children at the time but police said their parents were on the property. Authorities have launched a criminal investigation but are yet to name any suspects, or confirm whether either of the girls' parents is under investigation.  

One of the sisters is said to have been pronounced dead at the scene. Reports suggest CPR was attempted on the other sibling, who was pronounced dead on arriving at hospital. 

The sisters, Elena and Glory, were found unconscious, underwater, by a maintenance worker

The pool at the Ridgeview Apartments in Sherman, Texas

Eyewitness Carrie Curry told DailyMail.com on Thursday that she saw one of the girls floating and the other at the bottom of the pool.

She said one of the two was wearing a pink blouse and diaper when pulled lifeless form the water. 

She added that she is shocked that the toddlers were able to get inside the pool, which has a gate with a latch. 

The Lungmili Post, a Myanmar newspaper based in Boise, Idaho, identified the girls and reported that their brother died earlier this year from an unspecified illness, citing a source close to their family.

The family's church, Grayson Chin Baptist, held a service in the twins' memory on Thursday, and  the Burmese community in Sherman has posted several tributes to the girls on social media. 

The family's church, Grayson Chin Baptist, held a service in the twins' memory on Thursday

Helly Sui Len Tial wrote on Facebook: 'My heart is broken.

'Their son's death coincided with the death of my father... he was only 6 months old. 

'Elena and Glory, may you rest in peace! May the Lord comfort the parents!!'

North Texas has seen multiple drowning this summer, including that of as a six-year-old boy.