Add as a preferred source on Google Add Us On Google Add Us On Google Add as a preferred source on Google ST. CLAIR COUNTY, Ill. (First Alert 4) - A partnership has been made in the Metro East as MetroLink services prepare to expand into MidAmerica St. Louis Airport. The Mascoutah Police Department has officially become the fifth department to support MetroLink security. The move is part of more than $4 million in law enforcement services funded by the St. Clair County Transit District. The expansion is set to begin in September #firstalert4 #crimewatchstlouis