BANGKOK (AFP) -- A leading human rights group on Wednesday urged Myanmar's junta to free 70 activists currently on trial, after the military regime handed down a string of hefty jail sentences to dissidents.

At least 23 people arrested after last year's anti-junta demonstrations were given prison sentences on Tuesday, with most condemned to 65 years behind bars at Yangon's notorious Insein Prison, according to family friends and a lawyer.
New York-based Human Rights Watch called the trials ""unfair,"" and said the detainees should not be punished for taking part in the peaceful protests in August and September last year, which were suppressed by the military.
""These last few weeks show a more concentrated crackdown on dissent clearly aimed at intimidating the population,"" said Elaine Pearson, deputy Asia director at Human Rights Watch.
""These peaceful activists should not be on trial in the first place, let alone thrown in prison for years after unfair trials.""
The group said more than 70 dissidents -- monks, nuns, journalists and labor activists -- had been on trial over the past two weeks, mostly in secret hearings with family members barred, and in some cases with no legal representation.
The military regime has promised to hold elections in 2010, and Pearson said the convictions were likely an attempt to stifle any dissent ahead of the polls, which critics say aim only to entrench the army's power.
""Burma's leaders are clearing the decks of political activists before they announce the next round of sham political reforms,"" Pearson said, referring to Myanmar by its former name.
Myanmar has been ruled by the military since 1962, despite an election win in 1990 by Aung San Suu Kyi's National League for Democracy (NLD) party.
They were never allowed to govern and the junta has kept Nobel peace prize winner Aung San Suu Kyi under house arrest for most of the intervening years.