AKIPRESS.COM - The search for an Argentine naval submarine that went missing with 44 crew on board is being hampered by bad weather conditions, officials say.

Teams from several countries have intensified their efforts in the South Atlantic to find the ARA San Juan submarine, which vanished on Wednesday, BBC reported.

The US Navy has sent a second ship with special tracking equipment and deep-sea rescue modules to join the search.

The vessel disappeared 430km (267 miles) off the Argentine coast.

On Saturday, several satellite signals thought to have come from the sub were detected near the Valdez peninsula. A Nasa research plane was used in an attempt to trace the location but was unsuccessful.

Rescue teams have also been hindered by heavy winds and high waves.