Four people were placed under house arrest on Wednesday for alleged bribery linked to reconstruction contracts following the 2009 earthquake in L'Aquila in central Italy which killed 309 people, police said.

Four more people have been notified they are under investigation, including the quake-struck city's deputy mayor, Roberto Riga, and a local official in charge of restoring damaged monuments, Vladimiro Placidi.

Police said the eight people under investigation received a total of 500,000 euros ($680,000) in kickbacks from construction firms.

They are also accused of falsifying papers to receive 1.2 million euros in public funds and one is suspected of profiting from the sale of post-quake housing.

L'Aquila and the surrounding area in the Apennine mountains were devastated by the earthquake measuring 6.3 on the Richter scale and many buildings in the city centre still lie in ruins, with few signs of the hundreds of millions of euros spent on reconstruction.