CAIRO — Forces loyal to a Libyan commander who rules the eastern half of the country and who was behind a year-long military attempt to capture the capital, Tripoli, said they released on Thursday a Turkish-owned vessel seized last week, a military spokesman said. 

The Jamaica-flagged cargo vessel, Mabouka, was let go after local authorities questioned its crew and had them pay a fine for violations of sailing rules in Libyan waters, the spokesman for Libya's east-based forces, Ahmed al-Mosmari, wrote on his official Facebook page. He did not mention the amount of the fine. 

The seizure of the Turkish ship threatened to escalate tensions in the conflict-stricken North African country, since Turkey is the main supporter of the rivals of the east-based forces, the U.N.-backed administration in Tripoli, in western Libya. 

Turkey's Foreign Ministry had warned about "dire consequences" and called on east-based commander, Khalifa Hifter, and his forces to allow the ship to resume its planned voyage,

The oil-rich Arab country country has been split west to east since it descended into chaos following the 2011 uprising that ousted and killed longtime dictator Moammar Gadhafi.

The vessel was stopped on Saturday after it had tapped into Libyan waters without a prior permission sailing into a "no-sail" zone in Libyan waters, Mosmari wrote. He had said earlier that the crew included nine Turkish sailors, seven from India and one from Azerbaijan, and that it did not respond to calls from the naval forces.

The private security firm Dryad Global said the vessel was sailing from Egypt's Port Said to Libya's Mediterranean city of Misrata and that satellite imagery on Tuesday morning showed the vessel was held at Ras al-Hilal port, which is controlled by Hifter's forces. 

Hifter's forces launched an offensive in April 2019 to try and capture Tripoli from the U.N.-supported government. Throughout his march on the capital, Hifter had the backing of Egypt, France, Russia and the United Arab Emirates. However, his campaign collapsed in June, when Tripoli-allied militias, with heavy Turkish support, gained the upper hand in the fighting.

In October, the warring sides agreed to a U.N.-brokered cease-fire, a deal that envisioned the departure of foreign forces and mercenaries from Libya within three months.

Hifter's forces stopped the Jamaica-flagged cargo vessel, Mabrouka, on Monday off the eastern port town of Derna,