BURLINGTON (AP) -- A special police unit is investigating the circumstances that led to an infant being hospitalized in a coma.

Burlington Police Chief Michael Schirling says the Chittenden Unit for Special Investigations began working on the case early Tuesday.

The name of the 20-day-old boy has not been released.

Rescue crews were called to a city home just before 1 a.m. Tuesday and took the unresponsive infant to the hospital.

Detective Lt. Art Cyr tells the Burlington Free Press (http://bfpne.ws/1mFMb1z ) that rescue personnel were able to revive the baby.

Doctors are trying to determine what, if any, medical condition the child may have experienced.

The Burlington case is separate from that of a 2-year-old Shelburne boy who died Tuesday.

Police are investigating the circumstances of that case as well.