Tripoli, Libya (CNN) -- Libya said Monday night it had taken control of a North Korean-flagged tanker that had docked in a rebel-controlled oil port, but rebels dismissed the government's claims.
Culture Minister Habib al-Amin told reporters at a late-night news conference that government forces skirmished with rebels in speedboats as the ship left port Monday morning. The rebels were pushed back and government troops boarded the ship, which is loaded with what the United States said is "illicitly obtained oil."
There was more shooting Monday night in connection with the disputed tanker but the ship was secure, al-Amin said.
The rebels, meanwhile, told Libyan television that they still were in charge of the tanker and it was still docked at the port.
Libyan 'force' goes after threatened oil tanker
The dispute is one snapshot in the bigger picture of who controls -- and who profits from -- Libyan oil sales.
The vessel, dubbed Morning Glory, docked late Friday night in the port of As-Sidra in the northeastern part of the African nation.
While the ship was flagged in North Korea, it is unclear who actually owns the vessel.
Libya has seen its oil exports shrink to just 12.5% of its output since the revolution two years ago that led to the death of longtime leader Moammar Gadhafi.
Since the revolution, the government in Tripoli has struggled for control of the North African nation.
Tripoli had entrusted militia leader Ibrahim Jadran to safeguard some crucial oil ports. But eight months ago, he and his men seized them, blocked oil exports, and demanded more autonomy and shared revenues for his eastern region.
"We used to be part of that government until the corruption became so visible, and the government started to sell oil without measuring units, and ... we became certain that such a government is not credible and unable to rebuild the state," Jadran, 32, told CNN's Christiane Amanpour in January. "That's why we declared independence of our province and we started to seek our fair rights."
There is a lot at stake, given the Libyan government's precarious state and the wealth of natural resources in the country. Libya is thought to have Africa's largest proven oil reserves. The country produced 1.6 million barrels per day after the revolution only to have that output slow to a relative trickle of fewer than 200,000 barrels per day by the end of last year.
The government has said the disrupted oil production, from the seizures of ports as well as protests and strikes at other oil facilities, is costing the country $130 million a day.
The oil at the center of the current As-Sidra port situation belongs to Libya's National Oil Corporation and its partners, which U.S. State Department spokeswoman Jen Psaki notes includes U.S. companies. She said taking the oil amounted to theft from the Libyan people.
"Any oil sales without authorization from these parties places purchasers at risk of exposure to civil liability, penalties and other possible sanctions," Psaki said.
Libya's government has threatened force against ships that entered the rebel-controlled oil ports before on several occasions. But despite ultimatums to such ships, those deadlines came and went with no action from Libyan officials.
CNN's Jomana Karadsheh reported from Libya and CNN's Steve Almasy reported and wrote from Atlanta. CNN's Jamie Crawford contributed to this report.