Memory Leak while opening the XPS document in DocumentViewer

FilePath is XPS file name

xpsDoc = new XpsDocument(FilePath, FileAccess.Read, CompressionOption.NotCompressed);


FixedDocumentSequence fixedDocumentSequence = xpsDoc.GetFixedDocumentSequence();                
//I am getting an memory leak in the above line of code

DocViewer.Document = fixedDocumentSequence as IDocumentPaginatorSource;