(CNN) -- Colorado law enforcement officials announced Wednesday that a 12-year-old Burlington boy has been taken in custody in connection with the deaths of his parents and the critical wounding of two siblings.

The boy, whose name has not been released, has not been formally charged, nor is it clear what charges he might face. On Tuesday night the boy called 911 to report that at least three people in his house had been shot, according to police.

Burlington is a town of less than 4,000 near the Colorado-Kansas border.

"As a result of the investigation we have conducted so far, we are here this afternoon to announce that the 12-year-old family member who placed the 911 call from the residence has been taken into custody," said Colorado Bureau of Investigation Division Director Steve Johnson, in a prepared statement.

"The case has been referred to the District Attorney's office for the filing of formal charges," Johnson stated. "There are no other suspects at this time."

Investigators responded to the boy's 911 call around 6:40 p.m. on Tuesday, law enforcement officials said. Upon arriving, they discovered the bodies of the boy's parents, Charles Long, 50, and Marilyn Long, 51.

Officers also found two critically wounded children: a 5-year-old girl and a 9-year-old boy, whom authorities identified as siblings of the boy in custody.

The children, whose names have not been released, were taken to an area hospital and later transferred to a facility in Denver.

Authorities released few details about the investigation. A judge has issued a gag order and sealed the records in the case, including warrants, affidavits and the 911 tape. A coroner's report on the cause of death is pending.

Colorado law dictates that charges must be initially filed in juvenile court since the accused is 12 years old. However, the law does permit the district attorney to request that the case be moved to district court.

The prosecutor handling the case, Bob Watson, district attorney for Colorado's 13th Judicial District, said he has 72 hours to file formal charges against the boy.

John Branch contributed to this report