TRIPOLI, Libya (AP) — Libyan officials said that government forces on Monday took over a North Korean-flagged oil tanker docked at a terminal held by a regional militia, where it had been attempting to load oil. The militia, however, denied the government had taken the ship.

The standoff at al-Sidra, one of Libya’s main oil export terminals, has been a major challenge to the authority of the central government. The port has been held for months by eastern fighters demanding more regional autonomy from Tripoli. The incident involving the tanker marks the easterners’ first attempt to sell oil.