MOUNT VERNON — Knox County residents needing to mail 2009 tax returns by midnight tonight might need to make a drive to Columbus if forms are not dropped off in Mount Vernon by 5 p.m.

The Mount Vernon Post Office will be canceling letters until 5 p.m. with today’s date for those dropped off at the office or the drop-off boxes on North Mulberry Street by 5 p.m.

The traditional after hours drop-off in Columbus on Twin Rivers Drive will be closed tonight due to construction in the area. However, the post office on Stelzer Road, near Port Columbus International Airport will be open until 11 p.m. and the office at 2323 City Gate Drive will be open until midnight.