Story highlights More than 300 people died in the April 2009 earthquake in L'Aquila

Scientists were asked to assess the risk after increased seismic activity

They did not predict the major earthquake that hit the centuries-old city

Prosecutors say they gave a generic and ineffective assessment of the risk

Seven people went on trial for manslaughter Tuesday in Italy, accused of failing to predict an earthquake that killed more than 300 people in L'Aquila in April 2009.

The seven -- six scientists from the Italian National Institute of Geophysics and Vulcanology and a member of the Civil Protection Agency -- were members of a governmental panel that prosecutors accuse of giving a "rough, generic and ineffective assessment of the seismic risk."

The seven, members of a so-called "major risks" panel, published "inaccurate, incomplete and contradictory information about the dangers of seismic activity undermining the protection of the population," prosecutors said.

The first hearing Tuesday morning in L'Aquila's tribunal was devoted to technical matters and claims by injured parties.

The city of L'Aquila has requested 50 million euros ($68 million) in compensation.

Only one defendant was in court, the vice president of the panel, Bernardo De Bernardinis. "I thought it was important to be here, not only because this is my turf but also to underline the professionalism ... of the other public officers," De Bernardinis told reporters.

The trial has attracted the attention of the scientific world.

The American Association for the Advancement of Science (AAAS) wrote to Italy's President Giorgio Napolitano in June last year to express "concern" over the indictment of its Italian colleagues.

"The charges against these scientists are both unfair and naive," the letter said. The basis of the indictments appears to be that the scientists failed to alert the population of L'Aquila of an impending earthquake. However, the letter continues, "there is no way they could have done that credibly."

Lawyer Marcello Melandri is defending Enzo Boschi, who was president of the National Institute of Geophysics and Vulcanology at the time of the quake.

Melandri denies that it's a trial against science, saying: "Professor Boschi simply said that the earthquake is unpredictable, that it could or it could not happen."

The Civil Protection Agency had organized a meeting of the major risks panel in L'Aquila on March 31, 2009, amid concern among the city's residents over ongoing seismic activity.

After that meeting some members of the commission made reassuring statements to the press.

In particular De Bernardinis said in an interview with a local TV station that the scientific community was "reassuring" him, and that the numerous tremors were in some ways a good thing, as they released seismic energy.

The interview concluded with a joke. "Meanwhile, let's go and have a glass of wine," the journalist said. "Absolutely!" De Bernardinis replied.

Six days later, the magnitude-6.3 quake hit the city and surrounding areas, causing wide destruction and loss of life.

Eugenio Carlomagno is among the citizens of L'Aquila to feel let down by the panel.

"There are big responsibilities that this trial has to establish. No one alerted us, there were no evacuation plans that could have saved lives," he told CNN.

"It's not a matter of drinking a glass of wine, it's a matter of respecting rules."

The next trial session was scheduled for October 1.