The Foreign Ministry upgraded its travel warning Friday for the Solomon Islands, urging Japanese people to leave Guadalcanal and postpone visits to other parts of the islands.

The ministry upgraded the advisory for Guadalcanal to level 4 from level 3 on its scale of 5. Level 3 urged Japanese to put off visits to the island.

The advisory for other parts of the Solomons was raised to level 3 from level 2, which called for postponing visits for sightseeing and other “nonurgent” purposes.

A group of gunmen associated with an ethnic group called the Malaita Eagle Force continue to hold Prime Minister Bartholomew Ulufa’alu.

The Solomons — a chain of 10 islands northeast of Australia — have been racked by ethnic violence between Guadalcanalese and Malaitans since mid-1998, when the Gudalcanal Revolutionary Army was formed.