The United States Secretary of Defense on Tuesday apologized to Japan for the series of accidents involving military helicopters that has taken place on the island of Okinawa, in southern Japan, and has led to resentment among the local residents.

The apology of Jim Mattis to his Japanese counterpart Itsunori Onodera took place after a series of mishaps involving US military equipment and only a day after the emergency landing of a helicopter on an Okinawan beach, a spokesperson from the Japanese Defense Ministry confirmed to EFE.

Onodera urged Mattis to take measures so that such accidents are not repeated in the future and ensure that all military equipment is inspected, given the growing discontent among the residents of the island, who have been demanding the relocation of the US military base there.

In Dec. 2017, a child was injured at an Okinawan school after the window of a US military helicopter, which was flying to a nearby base, fell on a school's playing field.

The discontent has been further fueled by crimes committed by members of the US armed forces and other workers at the bases, which include rapes and murders.

Most of the residents in Okinawa - which houses over 70 percent of the US military installations in Japan and over half the nearly 48,000 American troops in the archipelago - have demanded that the base be relocated outside the prefecture.