Year-over-year net income at Newton-based REIT Government Properties Income Trust (GOV) roughly doubled in the fourth quarter on the strength of a more than 40 percent jump in rental income.

The company, which owns properties nationwide that are majority leased to the federal government and other government tenants, reported $13.2 million in net income in the fourth quarter, up from $6.5 million during the same period last year. The company said its 2010 fourth quarter results included a one-time charge of $3.8 million related to debt extinguishment.

In the fourth quarter, rental income rose to $51.7 million from $36.9 million in 2010. The $14.8 million in increased rental revenues helped offset a roughly $10.8 million increase in year-over-year fourth quarter expenses, to $35.13 million from $24.36 million in 2010.

In all of 2011, GOV reported $46 million in net income, up more than 65 percent from 2010 net income of $27.8 million, according to a statement.