Bomb threats against Naval Station Norfolk and Joint Expeditionary Base Little Creek-Fort Story.

NORFOLK, Va. (WVEC) -- Security forces gave an "all clear" at Joint Expeditionary Base Little Creek-Fort Story after the installation received five bomb threats throughout the day Wednesday.

Naval Station Norfolk was also the target of a bomb threat, but a security sweep again found no sign of danger.

Naval Station Norfolk

The first threat of the day came in at approximately 6 a.m. at Naval Station Norfolk. The regional dispatch center received a call about a bomb threat at the naval base. In response to the threat, security deployed additional military working dogs to sweep various areas on base.

At approximately 7:45 a.m. a military working dog alerted on a vehicle in the vicinity of Pier 14. In response, Pier 14 was put on security alert, and was secured to pedestrian and vehicular traffic. A shelter in place was for several buildings.

After an extensive inspection by the Explosive Ordnance Disposal team, the suspicious vehicle was cleared and deemed not to be a threat. The shelter in place was lifted, and all piers opened to vehicular and pedestrian traffic again.

JEB Little Creek-Fort Story

Five separate bomb threats were called in to Joint Expeditionary Base Little Creek-Fort Story. The harbor was secured, but the base was not locked down.

The first threat was called in at 9:19 and targeted USS Whidbey Island (LSD-41).

A second bomb threat was called in at 9:55, targeting the Admiral Joel T. Boone Branch Medical Clinic. The clinic was evacuated as a precaution and following a security sweep, returned to normal operations.

A third call came in at 10:30 and targeted the USS Gunston Hall (LSD-44). Pier 16 was secured to all pedestrians and vehicular traffic, as well as the marina and harbor.

The fourth call came in at 10:55 for the Personnel Support Detachment building. The facility was evacuated as a precaution, but has since been cleared and returned to normal operations. Update: 4 of 5 threats cleared at JEB Little Creek Fort Story. Security forces still sweeping USS Oak Hill. #13newsnow — Jemie Lee (@13JemieLee) August 2, 2017 A fifth bomb threat was called in that targeted USS Oak Hill (LSD-51) at 1:11 p.m.

USS Whidbey Island was cleared at 12:27 p.m., while USS Oak Hall was cleared by 5 p.m.

It was not clear if the threats against the joint expeditionary base were connected to the bomb threat made against Naval Station Norfolk.

Navy Region Mid-Atlantic said in a news release: Naval Criminal Investigative Service (NCIS) is conducting a thorough investigation to the source of the calls and those found to have called in false threats will be prosecuted to the full extent allowed." Anyone with information about the threats or the person or people responsible for making them can contact NCIS with an anonymous tip: Text to 274637 (CRIMES) Type “NCIS” at the beginning of your text message. Type and send your message including as much detail as possible to ensure the tips can be effectively investigated. You will receive a text with an alias code. This will be your tipster identity code which can be used for follow-ups.

The bomb threats come just two days after a possible diver was reportedly spotted in the water in a secured area near Pier 7 of Naval Station Norfolk.

The piers were locked down for much of Monday and a search was conducted into the early morning hours of Tuesday. No diver or other suspicious activity was ever found, and normal operations at the naval base resumed on Tuesday.

Nearly 60 ships are based in Norfolk, including the fleet's newest and most technologically advanced aircraft carrier, the USS Gerald R. Ford.

The carrier returned to its pier recently after successfully testing new equipment that launches and lands jet fighters.