Somali pirates freed a Greek-flagged tanker carrying 2 million barrels of oil Monday, a day after the biggest ransom yet paid to them was dropped onto its deck, the pirates and a maritime official said. The Maran Centaurus was seized on Nov. 29 with 16 Filipinos, nine Greeks, two Ukrainians and a Romanian on board. An aircraft dropped a ransom believed to be between $5.5 million and $7 million onto the vessel on Sunday, officials said. “We have agreed to solve our disagreements and release the ship. It is free and sailing away now,” one of the pirates, Hassan, said. “The crew are all safe.” Another pirate and a regional maritime official confirmed that the tanker, hijacked near the Seychelles archipelago in the Indian Ocean, was freed on Monday. A dispute between two rival pirate groups over the spoils had delayed its release. Ecoterra International, a Nairobi-based group that monitors shipping off Somalia, said two pirates had been killed in a gun battle with a rival gang as they returned to shore. “The stash of the record-breaking ransom ... is reportedly now held in a heavily guarded house in Haradheere,” it said, adding that the pirate-run port was now very tense because the sharing of the funds had not yet taken place.