国际英语新闻：S Korea steps up efforts to rescue missing sailors

The KBS quoted a military official as saying that the incident might result in significant casualties because most of the crew members were likely asleep or resting inside the ship when the explosion took place at around 21:45 p.m. local time, just 15 minutes ahead of the ship's bedtime.

The sailors' bedrooms are in the lower back part of the ship, close to where the explosion occurred, and water likely entered the ship quickly after the explosion, he said.

Although the hopes seem dimming over the rescue of the missing sailors, the related operation will continue on Monday.

A U.S. warship will be sent to the waters to join the rescue operation on Monday, and the South Korean Navy's 14,000-ton Dokdo, Asia's largest helicopter carrier, will also take part in the search and rescue operation late Monday, Seoul's Yonhap News Agency quoted military officials as saying.

The exact cause of the incident has yet to be pinpointed, government officials said, noting that it can be determined only after the sunken ship is salvaged, which will need about one month.

President Lee Myung-bak on Sunday convened a fourth meeting of security-related ministers at the presidential office of Cheong Wa Dae, demanding for thorough investigation and releasing all of the probe results to the public so as not to leave any room for suspicions for the incident.

Lee also said the most important thing at this moment is to rescue more survivors, urging the government agencies to save more lives by all means based on the belief that our sailors are still alive.

Prime Minister Chung Un-chan paid an inspection to the island of Baekryeongdo, the closest island to the scene of the warship sinking. He pledged to mobilize all available resources and provide full support to help rescue operation and determine the cause of the incident, according to Yonhap.