Germany pledged Wednesday to rebuild a school in earthquake-hit central Italy as a probe intensified into why at least one primary school and other buildings collapsed, causing nearly 300 deaths.

The offer was made by German Chancellor Angela Merkel after a summit meeting with Italian Prime Minister Matteo Renzi in Maranello, the home of Ferrari, near Modena in northern Italy.

"As a government we want to give a hand," she said. "And the positive thing is that German businesses also want to contribute and the German football league wants to organise a (fund-raising) match," she said.

One of the buildings which collapsed in the quake was the Romolo Capranica elementary school in Amatrice, the small town hardest hit by the disaster.

The school was supposed to have been upgraded to modern anti-quake norms in 2012 and the National Anti-Corruption Agency (ANAC) is looking into how the contract for that work was awarded.

"We have identified several aspects of the tender process that are unclear," ANAC boss Raffaele Cantone told SKY TG24 news channel on Wednesday.

"I cannot go into specifics but we are now trying to check further in cooperation with the financial police."

Giuseppe Saieva, the prosecutor who has opened a preliminary investigation into possible culpable homicide in relation to the disaster, said no one was under investigation at this early stage.

A prosecutor in the neighbouring region of Marche on Monday announced an investigation into the collapse of a middle school, municipal offices and a post office in the village of Araquata del Tronto.

am/gw

FERRARI NV