Six inmates who took a warden and a guard hostage at a prison in Taiwan have killed themselves after a lengthy standoff with police, according to reports.

The prisoners, all of whom were serving lengthy sentences for murder, burglary or drug-related offenses, feigned illness to take two guards hostage. Once they had secured hostages, they forced their captives to give them access to the prison's weapons cache, which contained rifles, handguns and 200 rounds of ammunition, the BBC reported.

The alleged ringleader, Cheng Li-te, was a member of the notorious Bamboo Union, one of the country's Triad organized crime gangs.

Taiwanese newspaper the United Daily News reported that it had interviewed Cheng by phone during the crisis, according to the Associated Press. He said that the hostage-takers had complaints about unfair trials, low pay for work done by incarcerated prisoners and unfairness in the granting of medical paroles.

The hostage-takers had also demanded that former Taiwanese President Chen Shui-bian, who was convicted of embezzlement and taking bribes in 2009, be returned to prison. Chen was released on medical parole in January, the New York Times reported.

"We tried to use all kinds of means to persuade them to release the hostages so the incident could come to a peaceful end and to prevent an unfortunate situation. We regret that six people took their lives," said Wu Hsien-chang, chief of Taiwan's Justice ministry's corrections agency told AFP.

At about 3:30 a.m. Local time Thursday (2:30 p.m. EST Wednesday), the inmates released one of the hostages, the prison's chief guard, and multiple gunshots were heard. Just over an hour later, the inmates shot at police from a side entrance of the prison, according to the South China Morning Post, with police returning fire. More than 20 gunshots were heard.

At about 5:40 a.m., all six inmates had reportedly committed suicide, ending the confrontation after 14 hours. Hundreds of police officers had surrounded the prison, in the southern port city of Kaohsiung.

Deputy Justice Minister Chen Ming-tang announced that the inmates had taken their own lives early Thursday, but Taiwanese authorities have not released any evidence to document these allegations, according to Chinese news blog Shanghaiist.

The BBC's Cindy Sui in Taipei said that Taiwan's prison system has seen 18 percent more inmates in the past decade as drug offenses and convictions rise, and said that overcrowding is a serious problem.