FRANKFURT (Reuters) - German prosecutors have opened preliminary proceedings into alleged links between Morgan Stanley's (>> Morgan Stanley) top dealmaker in Germany and the former premier of the regional state of Baden-Wuerttemberg, relating to the state's purchase of shares in German utility EnBW (>> Enbw Energie Baden Wuerttemberg AG) in 2010.

The Stuttgart public prosecutor's office said "sufficient and actual clues have emerged" suggesting ex-premier Stefan Mappus could have made himself liable to prosecution for breach of trust, while Morgan Stanley's Dirk Notheis could have made himself liable to prosecution for aiding and abetting breach of trust.

In a statement on Wednesday it added several premises had been searched as part of the proceedings and a number of documents were seized.

Morgan Stanley said it was supporting the investigation.

Prosecutors are probing Notheis, 44, who ran Morgan Stanley's operations in Germany and Austria for more than three years, but was granted leave of absence by the bank last month following an uproar over emails he reportedly exchanged with Mappus.

German newspapers in June published copies of emails Notheis reportedly sent to Mappus in 2010, when the southwestern state was trying to purchase a stake in local utility EnBW from French energy group EDF (>> EDF).

The reports sparked a wave of criticism, in part because it highlighted the cozy relationship between bankers and politicians at a time when many Germans are up in arms about the role banks have played in the global financial and euro-zone debt crises.

The prosecutors also quoted a report by a government audit body which said the purchase price paid by Baden-Wuerttemberg for the stake in EnBW was at least 180 million euros ($220.6 million) too high.

According to the opinion of a separate report drawn up by auditors Warth & Klein Grant Thornton, which was mandated by the regional state's government to assess the deal, Baden-Wuerttemberg had overpaid by around 840 million euros, daily Handelsblatt reported on Wednesday. ($1 = 0.8160 euros)

(Reporting by Christoph Steitz and Philipp Halstrick; Editing by David Holmes)

Stocks treated in this article : Enbw Energie Baden Wuerttemberg AG, EDF, Morgan Stanley