Local reports suggest that a teenager was swimming within the sea with friends before the search was launched.
A teenage boy is believed to have been swimming within the area just left to the pier. A Coastguard helicopter is above the area conducting a mile-wide search of the scene.
Cleveland Police have cleared members of the public from the area while a multi-agency search operation has been launched.
Emergency services raced to the scene just before 7pm on Thursday 17th July which is located near to the West View area of Hartlepool.
The H M Coastguard Search and Rescue, Cleveland Police and RNLI are currently involved within the search.
Eye witnesses at the scene said three teenagers were swimming within the sea and only two came back out of the water.