The flood-ravaged city of Joso, Ibaraki Prefecture, failed to issue evacuation orders and advisories to about 350 households before a riverbank along the Kinugawa River collapsed Thursday, which may have delayed some from trying to reach safety, it was learned Saturday.

Asked why the orders were not issued earlier, a Joso city official said, "We don't know. It may be because we were thrown into confusion."

The evacuation order for the district east of the Kinugawa River was given after the bank collapsed, which occurred around 12:50 p.m. on Thursday. That left many of the residents stranded until they were rescued.

According to the city, there were about 450 households in the neighborhood of Misaka, which is made up of eight districts. The city issued evacuation order at 10:30 a.m. in two of the eight districts, notifying those residents there by loudspeakers several times to evacuate.

But the remaining six, which included about 350 households, were not instructed to evacuate until 2:55 p.m., or about two hours after the levee collapsed.

It has come to light that the city of Osaki, Miyagi Prefecture, where heavy rain also caused massive damage, failed to issue evacuation orders or advisories to some of its districts.

However, Hirotada Hirose, professor emeritus of disaster psychology at Tokyo Woman's Christian University, argued Joso's response was better than those of other municipalities hit by large-scale mudslides in the past. The city started issuing evacuation orders to some areas at 2:20 a.m., five hours before the weather agency issued a special warning on heavy rain, which probably saved many lives, he said.