US navy boat
A U.S. Navy riverine gun-boat patrols during the International Mine Countermeasures Exercise (IMCMEX) at the Middle East Gulf, in this May 13, 2013 photo. Iran detained 10 U.S. sailors aboard two U.S. Navy riverine boats in the Gulf on Tuesday in an incident that rattled nerves days ahead of the expected implementation of a landmark nuclear accord with Tehran. REUTERS/Hamad I Mohammed/Files

UPDATE: 5:57 a.m. EST – The Pentagon confirmed early Wednesday that all 10 American sailors detained by Iran Tuesday have now safely returned to U.S. custody and there are no indications that they were harmed during their brief detention by Iran.

A statement from the U.S. Naval Forces Central Command Public Affairs Office reportedly said that U.S. Navy will investigate the circumstances that led to the sailors' presence in Iran.

UPDATE: 5:45 a.m. EST – All 10 American sailors who were detained by Iran for straying into its waters are now on board the USS Anzio and are undergoing initial medical checks, CNN reported, citing a U.S. official. The sailors were reportedly escorted by Iranian boats to a rendezvous point in the Persian Gulf.

UPDATE: 5:03 a.m. EST – U.S. sailors, who were taken into custody after their boats entered Iranian waters Tuesday, have been released, Agence France-Presse reported Wednesday, citing Iran's Revolutionary Guard.

Local media repleased photos of the American sailors before their release.

Original story:

Iran's Revolutionary Guards Naval Commander (IRGC), Rear Admiral Ali Fadavi, said Wednesday that 10 U.S. Navy sailors, who were taken in custody after their boats entered Iranian waters, are likely to be released soon, Tasnim news agency reported. Fadavi’s comments came after Revolutionary Guards spokesman Ramazan Sharif dismissed talks of their prompt release, saying that the American sailors were being interrogated.

The American sailors -- nine men and one woman -- were being held at an Iranian base on Farsi Island in the Persian Gulf. U.S. officials reportedly said that some mechanical issue with one of the boats caused them to drift into Iranian territorial waters near the island, following which they were detained. Late Tuesday, Pentagon claimed that plans where being made for Iran to return the American sailors to a U.S. Navy vessel in international waters Wednesday.

Fadavi reportedly said that the release of the American sailors "won't take long" as investigations concluded "that this trespassing was not hostile or for spying purposes." He also added that they were waiting to receive "the required order, which probably will be their release."

"If it is determined, after the investigation is carried out, that their action was not intentional, another approach will be taken," Sharif said in an interview with Tasnim news agency earlier on Wednesday, according to the Associated Press. "But if it's determined, after they are debriefed and interviewed, that their entry (into Iran's territorial waters) was for intelligence gathering or irrelevant action, definitely the authorities will take the necessary measures."

Meanwhile, Fadavi told state television Wednesday that a U.S. aircraft carrier in the Gulf had acted "provocatively and unprofessionally" for 40 minutes by carrying out air and sea maneuvers after Iran arrested the American sailors.

Fadavi also reportedly said that Tehran has asked Washington to apologize for “violating” Iran’s territorial waters.

"Iran's Foreign Minister Mohammad Javad Zarif was in touch with U.S. Secretary of State (John) Kerry … Zarif took a firm stance as the sailors had violated Iran's territorial waters and asked the United States for an apology," Fadavi said, according to Reuters.