By Massimiliano Di Giorgio
ROME (Reuters) - Luca Lanzalone, chairman of Italian utility Acea, was put under house arrest on Wednesday in an inquiry into the construction of a long-delayed new soccer stadium for AS Roma.
Six people had been detained and three others, including Lanzalone, placed under house arrest on charges of bribery, illegal political financing, influence peddling and criminal association, Rome prosecutors told reporters.
The new stadium for Rome's main soccer club has been dogged by political and bureaucratic problems since the contract was signed in 2014 by Rome's then centre-left city council. Building work is due to begin this summer and be completed in 2021.
Politicians from the centre-left Democratic Party and Silvio Berlusconi's centre-right Forza Italia party were among those arrested, while a prominent 5-Star member of Rome's city council was among those placed under investigation.
Neither AS Roma nor Rome mayor Virginia Raggi of the anti-establishment 5-Star Movement, who was elected in 2016, are under investigation, prosecutor Paolo Ielo added.
Among those jailed was Luca Parnasi, the head of the construction company building the stadium, who did not respond to telephone calls for comment on Wednesday.
Raggi, who nominated Lanzalone as chairman of Acea, the company that supplies Rome with water, gas and electricity, said that any wrongdoing would be punished.
"We are on the side of legality, anyone who did anything wrong will have to pay," Raggi told reporters.
Acea was not available to comment.
Lanzalone, a lawyer, also undertook unpaid consultancy work for 5-Star during its negotiations with the company building the stadium. The Rome prosecutors alleged he accepted illegitimate promises of consultancy work from Parnasi's company worth some 100,000 euros ($117,740).
($1 = 0.8493 euros)
(Writing by Philip Pullella and Gavin Jones; Editing by Alexander Smith)