( CNN ) Nine foreign workers are believed to be in the hands of ISIS-affiliated militants after an attack on a Libyan oil field , according to officials . Libya 's internationally recognized government has blamed `` ISIS militias '' for the attack Friday in which the Al-Ghani oil field was set on fire . The kidnapped foreigners were working for VAOS , an Austrian-owned oil services company whose headquarters are in Tripoli , the Libyan capital . They include four Filipinos , an Austrian , a Czech and a Ghanaian , according to the Philippine foreign ministry . The Bangladeshi government said one of its citizens was also taken hostage . The nationality of the ninth worker was unclear . The abductions come amid Libya 's deteriorating security situation in which Islamic militias , some of them pledging allegiance to the extremist group ISIS , have thrived . Egypt carried out airstrikes against ISIS militants in Libya last month after the killings of Egyptian Christians who had been kidnapped while working in a Libyan city . The Philippine foreign ministry said Monday that its Tripoli embassy had `` stepped up coordination '' with the Austrian company and Libyan authorities `` to locate the abducted Filipinos and ensure their safe and immediate release . '' Martin Weiss , a spokesman for the Austrian foreign ministry tweeted Monday that `` credible sources '' had confirmed that the Austrian citizen and other international workers were in the hands of ISIS `` terrorists . '' The attack on Al-Ghani is the latest in a recent spate of violence by militants targeting oil fields in Libya . The Libyan National Oil Corporation said over the weekend that it had warned VAOS more than two weeks ago to leave the area because of security concerns . VAOS was n't immediately available for comment Tuesday . The Philippine foreign ministry said 52 other Filipinos are employed by VAOS but were relocated out of Al-Ghani `` much earlier '' and are now in Tripoli . Three other Filipinos have been missing in Libya since they were seized at the Mabruk oil field in February , the foreign ministry said . `` These cases underscore the escalating threat to the safety and security of Filipino oil workers in Libyan oil fields which have been targeted by armed groups in recent weeks , '' said foreign ministry spokesman Charles Jose . He said Philippine authorities were unsure at this point whether the kidnappers were ISIS members . CNN 's Jomana Karadsheh and Marilia Brocchetto , and journalists Ayman Kekly and Arlene Samson-Espiritu , contributed to this report .
The abducted workers were seized in an attack on an oil field recent weeks . They are from the Philippines , Bangladesh , Austria , the Czech Republic and Ghana . Militants have carried out a series of attacks on oil fields in last week .