Connecticut environmental officials are expanding the area being closed in a state forest in response to the discovery of Eastern equine encephalitis in human-biting mosquitoes. The state Department of Energy and Environmental Protection said Tuesday it is closing a 300-acre area in Pachaug State Forest in Voluntown, near Rhode Island. The agency announced last week that it had closed two campgrounds. The state agency said it’s the largest outbreak of Eastern equine encephalitis in mosquitoes since 1996. The state also will spray the area to battle the mosquitoes.