Engineering firm JGC Corp., whose employees are believed to have been taken hostage Wednesday by Islamist militants in Algeria, is just one of many Japanese companies making inroads in the resource-rich country.

"In the North African region, Algeria and Libya are the two important hubs for Japanese companies, not only because they have rich natural gas and oil resources, but also because (Japanese companies have been) involved in construction of infrastructure," Shuji Hosaka, a senior research fellow at the Institute of Energy Economics, Japan, told The Japan Times on Thursday.

Seventeen Japanese companies currently have offices in Algeria, many of them trading firms and general contractors, according to the Foreign Ministry. Many of them have been operating there for several years, the ministry said.