Suspicion about IS's involvement in the disaster is snowballing, the questionnaire said, and went on:

First, when and from whom did the IS was informed of the ferry Sewol sinking accident for the first time?

According to Kyunghyang Daily News, the director of the Chonghaejin Maritime Transport Company informed the IS of the accident at 09:10.

But the "prime minister" said on May 20 he knew that the IS received a report on the accident by telephone and it was made by a crewman of the ferry, the daily news said.

However, the IS has asserted that it heard the news of the accident through radio at 09:44.

The IS, which has made lies, should make clear the fact immediately.

Second, has the IS known the fact that it was the first organ to be informed of the maritime accident according to the "report system" as regards the ferry Sewol worked out in February 25 last year? Why was the exceptional channel for making reports to the IS built?

There are many accusations that it is against common knowledge that a non-governmental company should directly report the accidents to the IS.

The IS should clarify the reason why the system of making primary report to it was applied to the ferry Sewol only.

Gushing out is the criticism that the IS received a report about the accident before anyone else but did not take relevant measures, a neglect of its duty, the questionnaire said, demanding it make clear what it did after receiving the report.