WASHINGTON, June 11 (Reuters) - Four more U.S. states on

Tuesday joined the Justice Department's lawsuit against Apple ( AAPL )

alleging the iPhone maker is monopolizing smartphone

markets, the department said in a statement.

The four additional states were Indiana, Massachusetts,

Nevada and Washington state, the Justice Department said. The

original lawsuit was filed in March, with the agency being

joined at the time by 15 states and the District of Columbia.