High temperatures this summer have caused railway tracks to warp more often than in the past, leading to an increase in service delays in some parts of Japan, with operators taking extra safety precautions due to the heat.

On Aug. 1, it was found that rails had warped on a portion of the Kagoshima Line in Kumamoto Prefecture, leading to the suspension of operations between Uto and Yatsushiro stations while an investigation was conducted, NHK reported. Workers used large blocks of ice to cool the rails and restore the tracks.

Kyushu Railway said in a news release last week that delays are possible, as it might have to reduce train speeds or suspend operations in order to ensure safety.