Giuseppe Orsi, chief executive of the Italian aerospace and defence firm, Finmeccanica, has been arrested on corruption charges.
Giuseppe Orsi has been under investigation for embezzlement for several months. He has always denied any wrongdoing.
Prosecutors allege he profited illegally from the sale of 12 helicopters to India.
Shares in the company did not open for trade in Milan.
In a statement, Finmeccanica expressed solidarity with Giuseppe Orsi and said: “Finmeccanica confirms that management activity and the initiatives it has undertaken are continuing in an orderly fashion.”
Italy’s Prime Minister, Mario Monti, said in an interview with Italian television: “Magistrates will do their work. I’m sure they will do it thoroughly and in the best way possible.”
He added: “There is a problem with the governance of Finmeccanica at the moment and we will face up to it.”
Giuseppe Orsi, chief executive of the Italian aerospace and defence firm, Finmeccanica, has been arrested on corruption charges
Arrest warrants have been issued for two people living in Switzerland.
India’s foreign ministry said it had not been informed of the raid.
“We had asked the government of Italy through our mission in Rome for details of the investigation, but were told that it is a judicial process and the government of Italy is unable to share any information,” said foreign ministry spokesman Syed Akbaruddin.
“That remains the position even today.”
For Italy, it is the latest in a string of corporate scandals – including risky trades at the bank Monti Paschi di Siena and allegations of bribery at the oil services group Saipem.
The black box of Russian Sukhoi Superjet 100 that crashed into Mount Salak, killing all 45 people on board, has been found by Indonesian search team.
The plane vanished 50 minutes after taking off from Jakarta for a brief demonstration flight on 9 May.
Data from the black box, found about 100 m from the tail of the plane, could help explain the cause of the crash.
The voice and data recorder was badly burned and had lost its distinctive orange color.
The black box of Russian Sukhoi Superjet 100 that crashed into Mount Salak, killing all 45 people on board, has been found by Indonesian search team
Tatang Kurniadi, who heads the National Transportation Safety Commission, said the data from the black box would be analyzed in Indonesia with help from Russian experts.
It will take between two to three weeks for any details to be revealed.
Eight Russian pilots and technicians, Indonesian airline representatives and journalists were among those said to be on board the plane.
The plane took off from east Jakarta’s Halim Perdanakusuma airport at 14:00 on 9 May, on its second flight of the day.
At 14:50, it was recorded as dropping from 10,000 ft (3,000 m) to 6,000 ft near Salak, a peak measuring 7,200 ft (2,200 m).
Villagers living in the area reported seeing a plane flying low into the mountain area.
The crash came with Sukhoi officials on an Asia-wide tour to show off their aircraft to airline firms.
The Superjet 100, a mid-range airliner that can carry up to 100 people, is military plane-maker Sukhoi’s first commercial aviation plane.
It was created by a joint venture, majority-owned by Sukhoi, with Italy’s Finmeccanica and a number of other foreign and Russian firms also involved.