LONDON - British private equity firm 3i Group agreed to sell Ambea to rival buyout firm Triton for 850 million euros ($1.16 billion), succeeding in its second attempt to offload the Nordic private healthcare company.

3i will sell its 75 percent stake in Ambea, owner of the Finland's Mehilainen and Sweden's Carema, it said in a statement on Tuesday. The deal will earn the firm 3.5 times its original equity investment.

Singaporean sovereign wealth fund GIC will also sell its 15.9 percent stake in the business, Ambea said in a separate statement.

3i had been considering a sale or a float of the business, Reuters reported earlier this month, with rival private equity firms Advent International and BC Partners considering bids for the group.

Investor AB had also been working with Goldman Sachs on a possible bid, banking sources said at the time.

We have been impressed by Ambea, the strength of its franchise and the quality of its management, said Triton partner Magnus Lindquist in a statement.

Ambea, which bills itself as market leader in the Nordic region in healthcare services, has 9,500 employees in Finland, Sweden and Norway. It recorded sales of 7.3 billion Swedish crowns ($1.0 billion) in 2009 and earnings before interest, tax, and amortization (EBITA) of 624 million.

Under 3i, Ambea has made more than two dozen acquisitions and has doubled net sales since 2005.

3i had explored a possible sale of Ambea in 2009 but shelved plans as the credit crisis froze activity in the European leveraged buyout market, one banking source previously said.

Triton, which operates out of offices in Stockholm, Frankfurt and London, counts Swedish diagnostics firm Phadia among its previous investments.

The transaction is expected to be finalized by end-March and requires approval from competition authorities, 3i said.

(Reporting by Simon Meads and Terhi Kinnunen; Additional reporting by Quentin Webb and Zaida Espana; Editing by Will Waterman and Louise Heavens)