(CNN) -- The mood was somber in South Korea Thursday as the nation officially honored the sailors who were lost when their warship went down near disputed waters off North Korea last month.
The funeral for the 46 sailors was held at Pyeongtaek naval base -- the home base for the Cheonan, the lost warship -- located on the Yellow Sea south of Seoul. The 1,200-ton corvette went down after a mysterious explosion tore it apart on the night of March 26.
The 2,800 attendees to the funeral included President Lee Myung-bak, who laid posthumous medals in front of portraits of the lost men; family members of those lost, surviving crew of the Cheonan, military officers, politicians and diplomats.
Fifty-eight men escaped the sinking ship. Forty of the ship's 104 crew members have been confirmed dead, and six more are believed dead, though they are still listed as missing.
Grieving family members, garbed in funeral black, sobbed quietly. Flowers were laid in front of the portraits, and incense burned. Hundreds of black and white balloons -- the color of the country's naval uniforms -- were released into the air.
"We will never forgive whoever inflicted this great pain on us," Adm. Kim Sung-chan, head of naval operations, said at the funeral. "We will track them down to the end and make them pay."
The bodies of the dead will be laid to rest at Daejeon National Cemetery, southeast of Seoul.
Elsewhere, ordinary South Koreans have been paying respects to the lost sailors at shrines set up in central Seoul and other cities. More than half a million people have reportedly visited the shrines.
But while there is sadness, there is anger, too, with some arguing for retaliation if North Korea is found to be responsible.
Both halves of the wrecked ship have been raised, revealing indications of an external explosion. Seoul has declined to point a finger of suspicion, North Korean state media have denied any involvement, and neither South Korean nor U.S. forces in Korea detected any unusual North Korean activity in the vicinity of the incident when it occurred. However, both circumstances and speculation point to a North Korean attack.
A team of South Korean military and civilian investigators tentatively concluded this week that an explosion at close range, and not a direct hit, caused the 1,200-ton patrol ship to go down. A U.S. military official said Monday that he believes a North Korean torpedo attack was the most likely cause for the sinking.
The media has been full of theories over how and why North Korea might have launched an attack, with many seeing it as revenge after a South Korean patrol boat fired at and hit a North Korean vessel in November. North Korean casualties from that incident are unknown.
"If Seoul really wants to deal with North Korea, it should not narrow the options at its disposal, but pressure the North with all of the choices it has, including military measures," said the Chosun Ilbo, Korea's top-selling newspaper, in an editorial Monday. "That is the only way to guarantee the effectiveness of diplomatic solutions."
Currently, the Yellow Sea floor is being scoured for fragments of the sunken ship, and for pieces of a torpedo or mine that would constitute direct forensic evidence of enemy action. Such evidence has not yet been found.
"So far we have recovered 330 fragments, but no fragments of a torpedo have been found yet," said Chung Jong-hyun, a former corvette captain and ex-head of the Ship Salvage Unit, which led the underwater recovery operation.
Chung told reporters Wednesday that a non-contact torpedo was the most likely cause of the explosion; it would be highly unlikely for a mine to strike a moving vessel, he said, whereas a torpedo is an aimed weapon. Moreover, the area in which the Cheonan went down is frequently traversed by both military and civilian shipping vessels.
The South Korean Navy has laid no mines in the area, a military official told CNN.
The situation leaves President Lee -- who has pursued a hard-line policy against North Korea that overturns a decade of engagement by his two predecessors -- facing his biggest policy challenge since taking office in 2008, due to the suspicion that his government is somehow playing politics with the tragedy.
"This is an unprecedented level of mourning, respect and honor given to people who have died on duty," Mike Breen, Seoul-based author of "The Koreans" told CNN. "Perhaps it is appropriate, but it is new and therefore a lot of people see politics in it rather than genuine concern about people who serve."
All Korean males have to do compulsory military service, but it is not a popular duty.
Compared to Lee, who has addressed the nation about the sinking in a radio broadcast, visited naval units and attended the funeral, then-President Kim Dae-jung underplayed the death of South Korean sailors after a 2002 naval clash, at a time when his government was actively seeking to engage the North in dialogue and commerce.
Moreover, there has been criticism that the navy was unprepared for a submarine attack, given the shallow waters of the Yellow Sea. "We thought it was not a good environment for submarines," said ex-captain Jung. "We have to change our ideas."