Investcorp, the Bahrain-listed alternative investment fund, has bought a portfolio of residential properties in the United States for around $300 million.

The deals, made through its U.S. based property arm, bring the fund's total purchases of properties in the country in the last 12 months to over $850 million, it said in a statement.

The latest properties, which total more than 2.1 million square feet, are in Washington D.C., Orlando, San Diego and Baltimore. They include around 1,900 family and student housing units with an occupancy rate of about 96 percent, offering potential for stable cash flow, it said.

The improving U.S. economic picture will stimulate further real-estate investments by the fund, with its main target being suburban offices and multi-family residential units in the top 30 U.S. metropolitan areas, Investcorp's chief financial officer Rishi Kapoor told Reuters.

As of the end of 2014, Investcorp's real estate group had around $1.5 billion in assets under management globally.