TRIPOLI, Libya - Militants purportedly from the Islamic State of Iraq and Syria attacked an oil field near Libya's central coast, prompting a counterattack by the country's Islamist-backed government that included airstrikes, an official said Wednesday.
The militants swept down from the city of Sirte to attack the al-Dhahra oil field, trading fire with guards and blowing up residential and administrative buildings before retreating, said Mashallah al-Zewi, the oil minister in the Tripoli-based government.
"They surrounded the site from three different directions, and when guards ran out of ammunition, they stormed the place, looted everything and then bombed the buildings, leaving them in ruins," he said.
All employees and workers, including foreigners, were safely evacuated, he said.
Al-Zewi said that the field is run by al-Waha oil company and other American companies. Al-Waha said on its website that al-Dhahra is one of Libya's oldest fields, with production starting in 1962. Libya's state-run National Oil Corporation runs the field.
Officials believe the same militants were behind the February attack on Libya's al-Mabrouk oil field that killed 10 guards and saw seven foreigners abducted, including three Filipinos. French oil giant Total SA says it worked at that field until 2013.
Oil production dropped dramatically in Libya after the country's 2011 civil war that toppled dictator Moammar Gadhafi. Al-Zewi said Libya's daily production is now nearing 500,000 barrels a day.
Libya's internationally recognized government has been confined to the far east since Islamist-allied militias seized Tripoli last year and revived an earlier government. That's worsened militia violence and allowed militants allied with ISIS to gain control of Sirte and Libya's eastern city of Darna.
These ISIS-affiliated militants carried out a deadly attack on a luxury hotel in Tripoli in January, and in February released a video showing them behead 21 Egyptian Christians. The Egyptian military launched airstrikes on Darna in retaliation.
The government in Tripoli is led by Islamists. It has denied the existence of the ISIS affiliate. The clashes at al-Dhahra are among the first known instances of Libya's Islamist-allied militias battling the Islamic State affiliate.