Two tankers were attacked near the Strait of Hormuz, with at least one of them operated by a Japanese company, said Japan's Economy, Trade and Industry Minister Hiroshige Seko on Thursday. 

The Japanese government is looking into the incident and collecting related information, Seko added. 

One of the two tankers attacked, Kokuka Courageous, is confirmed damaged by a Japanese shipping company in Tokyo.

All 21 Filipino crew members of the Japan-operated 19,349-ton ship escaped safely in life rafts and are heading to the United Arab Emirates, according to the operator of the ship Kokuka Sangyo Co.

The company said that the ship was sailing in the Gulf of Oman near the UAE emirate of Fujairah en route to Thailand and Singapore from Saudi Arabia. Tokyo-based Mitsubishi Gas Chemical Co. said the tanker was carrying methanol.

"I don't know why our ship was attacked," said Kokuka Sangyo President Yutaka Katada. "I'm angry that lives were threatened."

The transport ministry said details of the attack and the extent of damage are not yet known, and the tanker is currently drifting without a crew.

The incident comes when Japanese Prime Minister Shinzo Abe has been visiting Iran to help ease tensions between Tehran and Washington.