Gunmen suspected of belonging to the Islamic State group attacked Al-Mabrouk oil field in Sirte, Libya on Tuesday according to National Oil Corp (NOC) spokesman Mohamed Al-Harari, Reuters reports. The attack is considered the second major attack of its kind seen in the country within a week. A French diplomat in Paris, who asked to remain anonymous, said he believed that four local employees were killed in the attack on Al-Mabrouk oil field, which is located south of Sirte on Tuesday night. He added that there were no French citizens among the dead. Spokesman for the oil guard force, Aly Al-Hassi blamed Islamists for the attack, saying: "The field is out of our control. Islamic State is controlling it." French Total Oil Corporation owns a stake in the site, but recently sold the contract to a Libyan company. Rival forces have been fighting for two months over control of the largest oil fields in Libya, Es Sider and Ras Lanuf on the Mediterranean coast. Total said it has already evacuated staff from the site in 2013 and has no employees in the site since July 2014. Militants claiming to belong to the Islamic State terrorist organization, which controls parts of Syria and Iraq, recently declared responsibility for an attack on the Corinthia luxury hotel in Tripoli last week, which killed nine people, including five foreigners.