Japanese engineering firm JGC Corp on Friday confirmed the safety of three of its workers, who were among the hostages in a gas field in Algeria, while saying other up to 14 employees were still unaccounted for.

JGC told reporters it had been able to contact three Japanese nationals via telephone adding that one foreign worker was also safe.

Chief Cabinet Secretary Yoshihide Suga told reporters that the government was still checking on the situation, according to Reuters. Prime Minister Shinzo Abe reportedly cancelled part of his scheduled Southeast Asian tour due to the hostage crisis, Kyodo news agency reported.

Algerian forces stormed the In Amenas gas plant on Thursday to free hundreds of hostages held by Islamists militants from northern Mali. The bloody assault resulted to the deaths of 30 captives, including several Westerners, and 11 militants.

Two Japanese, two Britons and a French national were among at least seven foreigners killed, a source told Reuters. Eight Algerians were also killed in the raid while nationalities of the rest and dozens who escaped were still unclear.

At least one Filipino was reported injured but managed to escape from militants, the Philippines’ Department of Foreign Affairs said Friday, adding that they are still verifying if any Filipino nationals were among those killed.

Western governments have lashed out for being kept in the dark by Algeria about the assault which resulted in several deaths, AFP reports. A US military drone had flown over the are while US officials are still investigating on the fate of American nationals.