An American International Group Inc. (AIG) unit completed the sale of its energy and infrastructure investment assets Tuesday, realizing net processes of over $1.9 billion.

The insurance giant's AIG Financial Product Corp. completed the sale of its lease equity interest in the Bruce Mansfield power generation plant operated by FirstEnergy Corp. (FE). The sale was part of the ongoing process to wind down AIG Financial Products' business.

AIG, 80%-owned by the government following its rescue of the company last September, has been actively working to restructure its operations by selling off various assets and businesses. AIG and its units have reached agreement or closed over 20 deals in the past several months.

The Mansfield sale follows recent closings on a tax equity interest in the Stanton wind farm in Texas and two lease equity interests in portfolios of rail cars operated by Burlington Northern Santa Fe Corp. (BNI).

On Friday, AIG reported it returned to the black after six straight quarters of losses as the second quarter's results were absent major write-downs which had been pressuring the company. The company said it saw stabilization in some of its businesses but continued weakness in its core insurance operations.

Shares were recently down 12% to $25.25 amid a broad market decline, led by the financial sector, as investors grow cautious ahead of the Federal Reserve's policy announcement Wednesday.

-By John Kell, Dow Jones Newswires; 212-416-2480; john.kell@dowjones.com