Abigail Hernandez Missing: FBI Joins Search for Teen

Abigail Hernandez is still missing five days after being seen leaving Kennett High School in North Conway, New Hampshire. Her mother issued an emotional plea on her daughter's 15th birthday yesterday.

"Happy birthday, Abi," Zenya Hernandez said in front of police headquarters. "Please come home. We miss you so badly."

The 15-year-old was last seen Wednesday walking home from school; authorities believe she arrived at her mother's rented condo on Village Way but disappeared. Zenya reported her missing, and a search began for the teen. The FBI has joined the search but have not turned up any evidence of her whereabouts.

"We are nowhere near done," Major Kevin Jordan told ABC News. "We are here to find Abi and to bring her home."

"We are here for one reason," Senior Assistant District Attorney Jane Young said at a press conference. "We're trying to put together a timeline of when she went missing, the day before she went missing."

Police are investigating the case as a "missing person" but unfortunately have not ruled out the chance of foul play. They have asked for the public's help in locating the teen and spent Friday distributing fliers with Abi's information in the hope that someone will remember seeing the girl.

"This is still nothing more than a missing person case, but we are leveraging every tool, every technique, and every resource we have in hopes of bringing young Abby home to her family," FBI Special Agent Kiernan Ramsey said at a press conference. "There is no piece of information too small or insignificant to help us locate Abigail. We continue to be asked what we know about the investigation and we continue to answer with what we don't know – and that it, 'Where is Abigail at this very moment.'"

Abigail was last seen wearing black leggings or yoga pants, a gray-striped, multi-colored sweater and black leather boots. Anyone with information is asked to call 1-800-CALL-FBI or (603) 356-5715.