MOSCOW - The crew and suspected hijackers of the Arctic Sea cargo ship arrived in Russia on Thursday after a maritime saga peppered with piracy and the hint of espionage.

Russian warships found the merchant ship in the Atlantic Ocean off the Cape Verde islands on Monday and Moscow said eight people -- nationals of Estonia, Latvia and Russia -- had been arrested for hijacking the vessel.

Ilyushin-76 military planes carrying 11 of the 15-member Russian crew and the men suspected of hijacking the Maltese-registered ship arrived at the Chkalovsky military airfield outside Moscow, local news agencies reported.

The suspected men were then taken under guard to Moscow's high-security Lefortovo prison, a Reuters reporter said.

Russia says the men had hijacked the ship on July 24 off the coast of Sweden and then threatened to blow it up if their ransom demands were not met.

After heading through the English Channel in late July, radio contact was apparently lost and the 4,000-tonne ship did not deliver its cargo to the Algerian port of Bejaia on August 4.

Maritime authorities had said the Arctic Sea disappeared, leading to speculation that the ship may have been carrying some sort of secret cargo that spies had tried to intercept.

Only after the Russian navy boarded the ship did the Malta Maritime Authority say the ship had never really disappeared and that maritime powers had been tracking it for days.

Four crew stayed aboard the vessel which is anchored off the Atlantic island, Russia's Foreign Ministry said in a statement.

(Writing by Amie Ferris-Rotman and Guy Faulconbridge; Editing by Angus MacSwan)