* Students testify no help came from crew
* Coastguard rescuers were passive, only pulling passengers out
* Crew in a state of panic, witness says (Adds testimony of witness who was on ship's bridge)
By Ju-min Park
ANSAN, South Korea, July 28 (Reuters) - Six teenagers who survived South Korea's worst maritime disaster in 44 years told on Monday how classmates helped them float free as water flooded their cabins despite crew instructions to stay put even as their ferry sank, killing more than 300 people.
The teenagers, whose names were withheld to protect their privacy, were giving testimony at the trial of 15 crew members, who face charges ranging from homicide to negligence for abandoning the sinking ship.
"We were waiting and, when the water started coming in, the class rep told everyone to put on the life vests ... the door was above our heads, so she said we'll float and go through the door and that's how we came out," one of the teenagers said.
"Other kids who got out before us pulled us out."
The ferry Sewol sank on April 16, killing 304 people, as many as 250 of them school children on a field trip. Twelve of their teachers were also killed.
The ferry was on a routine trip from the port of Incheon south to Jeju island, carrying students and teachers from the Danwon High School on the outskirts of Seoul as well as other passengers and cargo.
Another of the teenagers told how crew members had told passengers, "specifically the students of Danwon High School", to stay in their cabins.
"Water started to fill in and friends helped us move out," the student said.
Others described how coastguard officers waited outside the stricken ferry for passengers to swim out rather than go into the ship to try and rescue them.
"They were outside. They pulled us (onto boats) but they didn't come inside to help," one said.
"We said to ourselves, 'why aren't they coming in?'."
"MORE FISHERMEN THAN RESCUERS"
Another student said it appeared there were more fishermen involved in the rescue than coastguard. Like others, she said the crew should be punished severely for their actions.
"More than that, I want to know the fundamental reason why my friends had to end up like that," she said.
The six teenage survivors described how there were repeated orders not to move from their cabins. Orders to put on their life vests came much later and without any information about what was happening to the ship as it began to list sharply.
They were the first of 75 children who survived due to give evidence in the trial at the Gwangju court, which has been moved to Ansan south of Seoul to accommodate the students.
Five of them gave their evidence facing away from the court. One testified from another room via closed-circuit television.
The crew members on trial, including the captain, Lee Joon-seok, have said they thought it was the coastguard's job to evacuate passengers. Video footage of their escape triggered outrage across South Korea.
Two musicians from the Philippines who had been working on the ship testified that the crew appeared to be in a state of panic as they gathered on the ship's bridge as it started to list, making no effort to get passengers off the vessel.
"I remember them panicked and worried," one of the pair, who was identified only by her first name, Alex, told the court.
She said the captain was crouched and holding onto a metal bar, apparently shaking with fear, and a junior ship's officer at the helm when the vessel started to list was crying loudly.
The government of President Park Geun-hye was heavily criticised over the slow and ineffective handling of the rescue operation. Park has vowed to break up the coastguard and streamline rescue operations, which are now split between the police, coastguard and others, into a single national agency.
The disaster also sparked South Korea's biggest manhunt as authorities searched for Yoo Byung-un, the man at the head of a family business that operated the doomed ferry.
Yoo's badly decomposed body was identified last week after it was found by a farmer at an orchard last month.
Earlier on Monday, a close associate of Yoo, a woman identified by police only by her last name of Kim, was arrested after handing herself in. It was believed she helped him elude police after the disaster.
Another woman, the wife of Yoo's driver who was thought to have been with him during his final days at large, also turned herself in to police.
Kim's arrest came three days after police stormed an apartment on the outskirts of Seoul and found Yoo's elder son, Dae-gyun, who was wanted for embezzlement.
Yoo Dae-gyun was not believed to have been as actively involved in management of the family business as his younger brother, who is believed to be in the United States. He said he only learned of his father's death from police.
Extensive decomposition of Yoo Byung-un's body meant it was not possible to determine the cause of his death despite forensic and DNA tests, authorities said last week. (Writing by Jack Kim; Editing by Paul Tait and Robert Birsel)