L'AQUILA, Italy -- Defying assertions that earthquakes cannot be predicted, an Italian court convicted seven scientists and experts of manslaughter Monday for failing to adequately warn residents before a temblor struck central Italy in 2009 and killed more than 300 people.

The court in L'Aquila also sentenced the defendants to six years each in prison. All are members of the national Great Risks Commission, and several are prominent scientists or geological and disaster experts.

Scientists had decried the trial as ridiculous, contending that science has no reliable way of predicting earthquakes. So news of the verdict shook the tightknit community of earthquake experts worldwide.

"It's a sad day for science," said seismologist Susan Hough, of the U.S. Geological Survey in Pasadena, Calif. "It's unsettling." That fellow seismic experts in Italy were singled out in the case "hits you in the gut," Hough added.

In Italy, convictions aren't definitive until after at least one level of appeals, so it is unlikely any of the defendants would face jail immediately.

Other Italian public officials and experts have been put on trial for earthquake-triggered damage, such as the case in southern Italy for the collapse of a school in a 2002 quake in which 27 children and a teacher were killed. But that case centred on allegations of shoddy construction of buildings in quake-prone areas.

State TV noted that this was the first time prosecutors had brought a case based on the failure to predict an earthquake.

Among those convicted Monday were some of Italy's most well-known and internationally respected seismologists and geological experts, including Enzo Boschi, former head of the National Institute of Geophysics and Volcanology.

"I am dejected, desperate," Boschi said after the verdict. "I thought I would have been acquitted. I still don't understand what I was convicted of."

The trial began in September 2011 in this Apennine town, whose devastated historic centre is still largely deserted.

The defendants were accused in the indictment of giving "inexact, incomplete and contradictory information" about whether small tremors felt by L'Aquila residents in the weeks and months before the April 6, 2009, quake should have constituted grounds for a quake warning.

The 6.3-magnitude temblor killed 308 people in and around the medieval town and forced survivors to live in tent camps for months.

Many much smaller earth tremors had rattled the area in the months before the quake, causing frightened people to wonder if they should evacuate.

"I consider myself innocent before God and men," said another convicted defendant, Bernardo De Bernardinis, a former official of the national Civil Protection agency.

Prosecutors had sought convictions and four-year sentences during the trial. They argued in court that the L'Aquila disaster was tantamount to "monumental negligence," and cited the devastation wrought in the southern United States in 2005 when levees failed to protect the city of New Orleans during Hurricane Katrina.

Relatives of some who perished in the 2009 quake said justice has been done. Ilaria Carosi, sister of one of the victims, told Italian state TV that public officials must be held responsible "for taking their job lightly."

The world's largest multi-disciplinary science society, the American Association for the Advancement of Science, condemned the charges, verdict and sentencing as a complete misunderstanding about the science behind earthquake probabilities.

There are swarms of seismic activity regularly in Italy and most do not end up causing dangerous earthquakes, said AAAS geologist Brooks Hanson, deputy editor of the organization's Science magazine. He said that if seismologists had to warn of a quake with every swarm there would be too many false alarms and panic.

"With earthquakes we just don't know," Hanson said Monday. "We just don't know how a swarm will proceed."

Comments on Twitter about the verdict abounded with references to Galileo, the Italian scientist who was tried as a heretic in 1633 for his contention that the Earth revolved around the sun and not vice versa as Catholic church teaching then held. In 1992, then-Pope John Paul II declared that the church had erred in its ruling against the astronomer.

Defence lawyer Filippo Dinacci predicted that the L'Aquila court's verdict would have a chilling effect on officials tasked with protecting Italians in natural disasters. Public officials would be afraid to "do anything," Dinacci told reporters.