YANGON, Myanmar (AP) _ A prominent member of democracy leader Aung San Suu Kyi's political party died in prison after being tortured, an exiled student group said Monday.

Thein Tin, a member of the National League for Democracy's Yangon Township organizing committee, died in Insein Prison on Feb. 18 ``following physical and mental torture,'' the All Burma Students' Democratic Front said. His age was not given.

The military government denied the charges in a statement to The Associated Press in Bangkok.

It said Thein Tin had been hospitalized Dec. 3 with liver cancer at Yangon General Hospital. Due to failing health, Thein Tin was pardoned and released from his prison sentence Feb. 15 but died three days later at the hospital, the statement said.

The military government accused the students of spreading ``rumors and disinformation,'' a claim dismissed by the students.

``Thein Tin was tortured and his health was deteriorating when he was finally admitted to hospital. The (government) had long refused his requests for proper medical care,'' the students said.

Several NLD members have died in prison in the past several years. Human rights activists and aid workers have described conditions in Insein, near Yangon, as inhumane.

Thein Tin was arrested in March 1996 and charged under the State Protection Act, which allows jailing anyone ``to protect the country from the dangers of those who wish to harm the state.''

He was a student leader in 1962, when Gen. Ne Win, who seized power in a coup that year, attempted to violently crush student opposition to military rule.

The student group also said three students from Pathein, 100 miles west of Yangon, have been sentenced to 4 1/2 years hard labor for flying a peacock flag at their high school on Union Day, which celebrates unity among Myanmar's ethnic groups.

The peacock is the symbol of democracy in Myanmar, also known as Burma.

A government official said the students were sentenced for illegal and forced entry into a restricted area, resisting arrest and destruction of public property.