HTML W3C Validation kicks out validation error related to "&"

          Line 245,         Column 118:     & did not start a character reference. (& probably should have been escaped as &.)     …vt_captchasecurityimages.php?width=225&height=75&field=Security_Code&bgcolor=7…                ✉
          Line 245,         Column 128:     & did not start a character reference. (& probably should have been escaped as &.)     …securityimages.php?width=225&height=75&field=Security_Code&bgcolor=776415&tran…                ✉
          Line 245,         Column 148:     & did not start a character reference. (& probably should have been escaped as &.)     …idth=225&height=75&field=Security_Code&bgcolor=776415&transparent=0&bgimage=&g…                ✉
Line 245,         Column 163:     & did not start a character reference. (& probably should have been escaped as &.)     …=75&field=Security_Code&bgcolor=776415&transparent=0&bgimage=&gridfreq=50&grid…                ✉
Line 245,         Column 177:     & did not start a character reference. (& probably should have been escaped as &.)     …rity_Code&bgcolor=776415&transparent=0&bgimage=&gridfreq=50&gridcolor=CC2849&g…                ✉
Line 245,         Column 186:     & did not start a character reference. (& probably should have been escaped as &.)     …&bgcolor=776415&transparent=0&bgimage=&gridfreq=50&gridcolor=CC2849&gridorder=…                ✉
Line 245,         Column 198:     & did not start a character reference. (& probably should have been escaped as &.)     …415&transparent=0&bgimage=&gridfreq=50&gridcolor=CC2849&gridorder=behind&noise…                ✉
Line 245,         Column 215:     & did not start a character reference. (& probably should have been escaped as &.)     …&bgimage=&gridfreq=50&gridcolor=CC2849&gridorder=behind&noisefreq=10&noisecolo…                ✉
Line 245,         Column 232:     & did not start a character reference. (& probably should have been escaped as &.)     …q=50&gridcolor=CC2849&gridorder=behind&noisefreq=10&noisecolor=0099FF&noiseord…                ✉
Line 245,         Column 245:     & did not start a character reference. (& probably should have been escaped as &.)     …r=CC2849&gridorder=behind&noisefreq=10&noisecolor=0099FF&noiseorder=behind&cha…                ✉
Line 245,         Column 263:     & did not start a character reference. (& probably should have been escaped as &.)     …=behind&noisefreq=10&noisecolor=0099FF&noiseorder=behind&characters=5&charheig…                ✉
Line 245,         Column 281:     & did not start a character reference. (& probably should have been escaped as &.)     …10&noisecolor=0099FF&noiseorder=behind&characters=5&charheight=&font=fonts/MYT…                ✉
Line 245,         Column 294:     & did not start a character reference. (& probably should have been escaped as &.)     …=0099FF&noiseorder=behind&characters=5&charheight=&font=fonts/MYTYPE.TTF&textc…                ✉
Line 245,         Column 306:     & did not start a character reference. (& probably should have been escaped as &.)     …eorder=behind&characters=5&charheight=&font=fonts/MYTYPE.TTF&textcolor=E4D4AA"…                ✉
Line 245,         Column 328:     & did not start a character reference. (& probably should have been escaped as &.)     …rs=5&charheight=&font=fonts/MYTYPE.TTF&textcolor=E4D4AA" alt="security code" w…                ✉
Line 245,         Column 501:     & did not start a character reference. (& probably should have been escaped as &amp;.)     …ng" height="18" onClick="document.getElementById('capt1').src+='&ref=1'"></div>                &#9993;
Line 245,         Column 509:     An img element must have an alt attribute, except  under certain conditions. For details, consult guidance on providing  text alternatives for images.     …ng" height="18" onClick="document.getElementById('capt1').src+='&ref=1'"></div>