PHILADELPHIA (CBS) - A fifth teenager has been arrested in connection to the alleged gang rape of a 12-year-old girl inside a recreation center in Southwest Philadelphia.

Police confirm to Eyewitness News the last three arrests were made Thursday. Four of the juveniles, who are all between 14 and 15 years old, have been charged with Rape, Criminal Conspiracy, Simple Assault and related offenses. The fifth teen has not yet been charged.

Authorities say the first two teens were arrested and charged Wednesday.

The victim says she was attacked by a group of 14-year-old boys Monday night in a stairwell inside the Francis Myers Recreation Center (see related story).

The incident remains under investigation.