“I found out I was being investigated only now,” Scajola told Italian television on Tuesday.
Scajola denied any wrongdoing from the time he was a minister in the government of former prime minister Silvio Berlusconi.
Police searched Finmeccanica offices in Naples and Rome on Tuesday in relation to the arrest of Pozzessere, said one of the investigative sources, who requested anonymity because he was not authorized to speak publicly.
“It’s linked to the news of the arrest,” a Milan trader said, referring to the stock decline.
The probe, led by prosecutors in Naples, is one of several under way at Finmeccanica. Chairman and Chief Executive Giuseppe Orsi is also under investigation over a 560 million-euro ($730 million) Indian helicopter contract.
Orsi has vowed to stay in his post to clear his name but some political parties have raised questions about whether he should remain at the helm of the country’s second-biggest private group.
A meeting that was due to be held between Finmeccanica’s top executives and the government last week was cancelled.
Asked about Finmeccanica top management, Italian Economy Minister Vittorio Grilli said: “I have no comments to make.”