Athens - An appeals trial for four convicted members of a Greek far-left terrorist group, Revolutionary Popular Struggle, began on Wednesday at a top security prison in Athens.

The four convicted members of the group, three men and one woman, also known as ELA, are appealing their 25-year priosn sentences. All four were convicted in 2004 for being members of the group and were released on parole.

The trial is being held at a special court which is built inside top security Korydallos prison and is expected to last several months.

The terrorist group which has been active for the past 20 years is blamed for the murders of a policeman and a supreme court prosecutor as well as for carrying out dozens of bombing attacks.

It was considered the second most deadly group after the far-left terrorist group November 17 which killed more than 20 people between 1975 and 2000.