A toddler died early this morning from injuries he suffered after plummeting from a third-floor apartment window in the Frankford section of Philadelphia last night, according to city police.

The boy had been critically injured after striking the pavement in the fall at 6 p.m. Sunday and was taken to St. Christopher's Hospital for Children.  Investigators in the special victim's unit confirmed he died overnight.

Police said the boy was inside the rear apartment of a home on the 1600 block of Foulkrod Street when he fell from an open window to the alley below.

Chief Inspector Scott Small told news crews that two adults were home at the time, but did not witness the fall.  Small did not say what relation the adults were to the child.

The incident was being investigated as an accident; homicide detectives said this morning that they were not involved.