TOKYO (AFP) - Prime Minister Shinzo Abe on Saturday ordered his government to do everything possible to ensure the safety of 10 Japanese nationals unaccounted for in the Algeria hostage crisis.
Mr Abe attended a meeting of a government taskforce shortly after arriving in Tokyo after cutting short a trip to South-east Asia.
"I would like you to do your best to confirm the safety of the Japanese and rescue them by using every possible means," he told top government officials at the meeting.
Al-Qaeda-linked gunmen, cited by Mauritania's ANI news agency, said they were still holding seven foreigners at a remote Algerian gas plant deep in the Sahara desert - three Belgians, two Americans, one Japanese and a Briton.
An Algerian security official put their number at 10.
However, more workers remain unaccounted for, and the fate of at least 10 Japanese nationals is unknown, according to Tokyo.
Mr Abe called for all-out efforts to collect accurate information on the situation and for close international cooperation to resolve the crisis.
The Islamist captors have demanded a prisoner swap and an end to French military action in Mali.
The meeting in Tokyo came shortly after a joint news conference in Washington involving US Secretary of State Hillary Clinton and Japanese Foreign Minister Fumio Kishida.
"The government of Japan has been requesting the government of Algeria to place the utmost priority on ensuring the safety and the lives of the hostages," Mr Kishida said.
International criticism of the haste with which Algeria launched a dramatic military assault to rescue the hostages has been mounting, after an Algerian security official said it had left dead 12 hostages and 18 kidnappers.
Japanese plant builder JGC, which has 78 employees at the site, said it had now accounted for 17 of them - seven Japanese and 10 others, including two Philippine nationals and a Romanian.
JGC president Koichi Kawana and other senior officials left for Algeria early Saturday.
"Since the safety of many more people has yet to be confirmed, I would like to confirm their safety based on firm and accurate information," Mr Kawana told reporters ahead of his departure.