US woman still alive after lethal injection dose, legal team says

Christa Pike has been on death row for more than three decades. ( AP: Tennessee Department of Correction )

A woman on death row in the US state of Tennessee is still alive after two doses of lethal injection, according to her lawyers.

Christa Pike was scheduled to be executed at a maximum security prison in Nashville at 10am on September 30, local time.

Her execution was delayed after a last-minute stay, with the Supreme Court ultimately clearing the way for it to go ahead a few hours later.

Her legal team has now said she is still alive more than an hour after the execution drug was administered.

Witnesses have been released from the Riverbend Maximum Security Institution, where the execution was held.

Emergency vehicles left Riverbend Maximum Security Institution after the execution was halted. ( AP Photo: George Walker IV )

Emergency service teams have been seen outside the prison and reportedly left the area with lights and sirens blaring.

Copyright for this text belongs to ABC Australia.